As with frameworks, here are my opinions on the concepts suggested so far. Unlike frameworks, there seem to be fewer suggestions, so I can afford to comment on all of them. (Ranking from 1 to 4, the different between 4 and 5 is personal taste.)
Hazards, examined three ways: Hazards are a deep enough topic to do a trio on, and the different ways the concept can be done will keep the trio from being homogenous. Somehow not very exciting to me despite that. ★★★★
Fearless Firsts: With the team preview addition, leads are relatively niche, so I'm not sure this is worth doing three of. Still, trying to resurrect the lead role is an interesting challenge. ★★★
Make Weather Great Again: Isn't this just Jumbao again? The one positive thing is trying to improve Hail needs multiple Pokemon, which the framework can help out with. ★★
Welcome to the Matrix: These effects are all really fun, and there are the right number of them to give each starter a specialty. I would give it 5-stars except that it would make the starters a bit too homogenous for my taste. ★★★★
Sides of the Same Coin: I really don't like the flavor of having all the starters have the same ability, and the concept itself is only ok. ★
Status Update: The CAP metagame has a lot of Pokemon that for some reason are resistant to status. I think the concept itself is additionally too broad, including Gravity, Follow Me, in addition to the standard statuses. The broadness does lend itself to the starter framework, if it can be defined better. ★★
These Shackles Make Me Mortal: There's a real risk here in making an ~immortal~ CAP, but that can be fun. Additionally, comparatively low stats are already a weakness, and not one that works much as a shackle. I like the generality. ★★
P.S. What's so counterintuitive about Vespiqueen's typing?
Specialized Forces: I don't like how generic this is - most Pokemon are one of the best at something, this doesn't narrow down the target very much, which also makes the questions it can also vaguer and less interesting. ★
Environment Control: Similar to the above, this is rather generic. "Hazards, examined three ways" is still broad enough to make three CAPs out of, but without opening out the concept to half of the metagame. The broadness also makes this less exciting. ★
Speed Demons: This concept has a good sized domain of potential CAPs. Can't think of much to say about it. ★★★
Pinch Me, I'm Dreaming: The framework, which seems to require pinch abilities, works well with this concept. I'm not sure it's easy enough to do three times, nor broad enough a concept to want to. It is exciting though. ★★★
Undiscovered Potential: I would enjoy making this, but it's not very specific/creative (I think Cyclohm had the same concept?). A good fall-back option though. ★★★
Typed Together: This jumps around some of the problems with the most obvious core concept. It's broad enough to do three times, and yet there's still a specific goal in mind for each one. ★★★★
Ultimate Rock-Paper-Scissors: I proposed this one, and I still like it near the best because it has a very defined goal for each Pokemon, and more than any other concept involves designing the CAPs as a single project rather than three concurrent ones. Contra Frostbiyt I think it's unlikely to happen automatically - Emboar is hardly who you think of as a Serperior counter, for example, nor Greninja as a Delphox counter, even though they counter each other's types. ★★★★★
The Bigger They Are: I like the name and the idea itself, and it's certainly broad enough to do three times. Somewhat indefinite in the beginning steps, but it's goal-oriented enough that's not a problem. ★★★★
Super Hax: Sorry, this isn't objective, but I just don't like hax, especially not if we do it three different ways. ★
Role Compression Madness: I'd like the project to avoid generic goodness, but this is a good topic on other metrics. ★★★
Once More, with Feeling!: Celebratory is the first thing that jumps out to me about this concept. The questions are ones I'd like to learn answers to, and looking back is fun. ★★★★★
Renewal: This is a difficult goal, but one that will be well-defined once a target is chosen for each. I don't mind if the CAPs don't last long at the top of the metagame. ★★★★★
Par for the Cores: This is The core concept for starters, one that works well with the framework, and is nicely targeted, but it won't bring very much new to CAP, and it'll be difficult to compete with the great cores out there with three Pokemon all with sub-par stats. ★★★
Death to the King!: With three Pokemon at our disposal, this is certainly uniquely possible. I would also enjoy a shake-up in the meta when CAPs are finished. (Running out of new things to say, but this is also goal-oriented, which will make the learning-experience better.) ★★★★
Astounding Ability Actualization (Triple A): The justification of starter-like BST viable Pokemon having abilities extremely synergistic with their roles is very persuasive, and I like how focused the concept is on the actualization of the abilities. ★★★★★
Set-Down: I think this is in fact an interesting concept - but as Frostbiyt points out it's already done by a few other CAP-metagame pokemon, and I don't think it's deep enough to do three differently-interesting ways. ★★
-ize/-ate is Our Fate: As with the above, I think this is a great concept, but not particularly tuned to the fact we're doing three different Pokemon. It'll be difficult keeping them distinct and not just going through motions. ★★
Hazards, examined three ways: Hazards are a deep enough topic to do a trio on, and the different ways the concept can be done will keep the trio from being homogenous. Somehow not very exciting to me despite that. ★★★★
Fearless Firsts: With the team preview addition, leads are relatively niche, so I'm not sure this is worth doing three of. Still, trying to resurrect the lead role is an interesting challenge. ★★★
Make Weather Great Again: Isn't this just Jumbao again? The one positive thing is trying to improve Hail needs multiple Pokemon, which the framework can help out with. ★★
Welcome to the Matrix: These effects are all really fun, and there are the right number of them to give each starter a specialty. I would give it 5-stars except that it would make the starters a bit too homogenous for my taste. ★★★★
Sides of the Same Coin: I really don't like the flavor of having all the starters have the same ability, and the concept itself is only ok. ★
Status Update: The CAP metagame has a lot of Pokemon that for some reason are resistant to status. I think the concept itself is additionally too broad, including Gravity, Follow Me, in addition to the standard statuses. The broadness does lend itself to the starter framework, if it can be defined better. ★★
These Shackles Make Me Mortal: There's a real risk here in making an ~immortal~ CAP, but that can be fun. Additionally, comparatively low stats are already a weakness, and not one that works much as a shackle. I like the generality. ★★
P.S. What's so counterintuitive about Vespiqueen's typing?
Specialized Forces: I don't like how generic this is - most Pokemon are one of the best at something, this doesn't narrow down the target very much, which also makes the questions it can also vaguer and less interesting. ★
Environment Control: Similar to the above, this is rather generic. "Hazards, examined three ways" is still broad enough to make three CAPs out of, but without opening out the concept to half of the metagame. The broadness also makes this less exciting. ★
Speed Demons: This concept has a good sized domain of potential CAPs. Can't think of much to say about it. ★★★
Pinch Me, I'm Dreaming: The framework, which seems to require pinch abilities, works well with this concept. I'm not sure it's easy enough to do three times, nor broad enough a concept to want to. It is exciting though. ★★★
Undiscovered Potential: I would enjoy making this, but it's not very specific/creative (I think Cyclohm had the same concept?). A good fall-back option though. ★★★
Typed Together: This jumps around some of the problems with the most obvious core concept. It's broad enough to do three times, and yet there's still a specific goal in mind for each one. ★★★★
Ultimate Rock-Paper-Scissors: I proposed this one, and I still like it near the best because it has a very defined goal for each Pokemon, and more than any other concept involves designing the CAPs as a single project rather than three concurrent ones. Contra Frostbiyt I think it's unlikely to happen automatically - Emboar is hardly who you think of as a Serperior counter, for example, nor Greninja as a Delphox counter, even though they counter each other's types. ★★★★★
The Bigger They Are: I like the name and the idea itself, and it's certainly broad enough to do three times. Somewhat indefinite in the beginning steps, but it's goal-oriented enough that's not a problem. ★★★★
Super Hax: Sorry, this isn't objective, but I just don't like hax, especially not if we do it three different ways. ★
Role Compression Madness: I'd like the project to avoid generic goodness, but this is a good topic on other metrics. ★★★
Once More, with Feeling!: Celebratory is the first thing that jumps out to me about this concept. The questions are ones I'd like to learn answers to, and looking back is fun. ★★★★★
Renewal: This is a difficult goal, but one that will be well-defined once a target is chosen for each. I don't mind if the CAPs don't last long at the top of the metagame. ★★★★★
Par for the Cores: This is The core concept for starters, one that works well with the framework, and is nicely targeted, but it won't bring very much new to CAP, and it'll be difficult to compete with the great cores out there with three Pokemon all with sub-par stats. ★★★
Death to the King!: With three Pokemon at our disposal, this is certainly uniquely possible. I would also enjoy a shake-up in the meta when CAPs are finished. (Running out of new things to say, but this is also goal-oriented, which will make the learning-experience better.) ★★★★
Astounding Ability Actualization (Triple A): The justification of starter-like BST viable Pokemon having abilities extremely synergistic with their roles is very persuasive, and I like how focused the concept is on the actualization of the abilities. ★★★★★
Set-Down: I think this is in fact an interesting concept - but as Frostbiyt points out it's already done by a few other CAP-metagame pokemon, and I don't think it's deep enough to do three differently-interesting ways. ★★
-ize/-ate is Our Fate: As with the above, I think this is a great concept, but not particularly tuned to the fact we're doing three different Pokemon. It'll be difficult keeping them distinct and not just going through motions. ★★