Banedon, all I can tell you from all this is to stop theorymoning and actually play with Cradily or play against it. It's actually a lot harder to get going than you're making it, seriously.
So I seriously tried using Cradily and I don't think I was wrong ...
The set I used was this one:
Cradily @ Leftovers
252 HP, 252 SpD, 4 Def
Rest
Curse
Rock Slide
Seed Bomb
It can set up on a whole heap of Pokemon. Top UU Pokemon it can set up on include non-Haze Milotic, Venusaur, Moltres, Arcanine (some variants), Spiritomb, non-Curse Registeel, some Mismagius and some Alakazam, and the list goes on and on and on. Cradily's special bulk is seriously good, rivalling even Chansey. For example, 252 SpA Modest Specs Alakazam Psychic vs. 252/252+ Cradily in a Sandstorm is 30.3% - 35.9%. So much for one of the most powerful special attacks in the tier. This makes Cradily a decent special wall at least.
That's from the special side. On the physical side Cradily is vulnerable - but it can wear its counters down. What makes it easier to wear down Cradily's counters than it is to wear down Cradily's counter's counters? There are several reasons. First is Sandstorm, whereby Pokemon like Arcanine cannot use Morning Sun nearly as effectively. Second, Cradily's counters generally do not get / use recovery and take far more from Cradily's attacks than they deal. For example, CB Scyther cannot switch into Rock Slide. It's also 4x weak to Stealth Rock, and since sandstorm is in effect it means Scyther will only be able to switch in once if Stealth Rock is on the field. Wearing CB Scyther down then isn't too difficult. Other counters, such as Hitmonlee, takes 49.8% - 58.9% from Seed Bomb. That is not cheap at all. Even if we accept that Cradily cannot predict right all the time, Rock Slide still does 23.2% - 27.4%. With 6% from sandstorm, 6% from SR and then any further damage from Life Orb, Hitmonlee takes a lot of damage very quickly. Against this, Cradily's counter's counters include Pokemon like Gligar (with Roost), Nidoqueen (at least has Leftovers) and Weezing (Pain Split / Rest). They should live longer than Hitmonlee, LO EQ Hitmonlee vs. Nidoqueen aside.
Switching out is certainly a bad thing most of the time, but after switching out the Cradily counter is forced to switch out itself. Cradily's counter usually cannot afford to overpredict because, short of a powerful STAB Close Combat, if you do overpredict and Cradily stays in, you're in trouble. Cradily's defenses increase quickly: CB Scyther U-turn fails to KO +1 Cradily: 55.9% - 66%. If you have to switch Scyther out, then switch Scyther back in, Cradily might've healed up already. Meanwhile pretty much all the Fighting Pokemon are hard-countered by Weezing. Also, sandstorm helps with scouting Trick a whole lot. For example, if Rotom switches in on Cradily, it takes sandstorm damage even if Stealth Rock isn't up. If it shows no Leftovers chances are it is choiced. So Cradily should switch out (go to Hippopostas). Even if Rotom is the SubSplit LO type, Cradily can easily switch back in later, when Rotom will not pose a threat until it gets multiple SpD falls from Shadow Ball.
Finally there is setting up alongside Cradily, especially if Cradily is asleep, but Cradily is really sturdy. Consider for example:
+1 Adamant LO Feraligatr Ice Punch vs. 252/0 +1 Cradily: 54.8% - 64.9%
+1 0 Attack Cradily Seed Bomb vs. 28/0 Feraligatr: 68.6% - 81.1%
What has happened to me in this situation is my opponent using Toxic on Cradily while Cradily is Cursing, and then switching out after I reveal Rest. On turn one of sleep, Feraligatr switches in. On turn 2 of sleep, Feraligatr gets its Dragon Dance (of course, if my primary checks are still alive, I'd go to them and conserve Cradily for late-game). On turn 3, Feraligatr Ice Punches, fails to KO and dies to Seed Bomb (SR + LO recoil + 2 turns of Sandstorm).
Here's another example:
+2 Timid Mismagius HP Fighting vs. 252/252+ Cradily in a sandstorm: 40.4% - 47.9%
+1 0 Attack Cradily Seed Bomb vs. 4/0 Mismagius: 62.2% - 73.7%
So Cradily Rests after Cursing once. On turn 1 of sleep, Mismagius switches in. On turn 2 of sleep, Mismagius Nasty Plots (if Mismagius subs now, it loses even worse to Cradily). On turn 3, Mismagius attacks, fails to 2HKO, and takes big damage. If it stays in, it dies on turn 4. Life Orb Mismagius is even better for Cradily, since there's a good chance it dies on turn 3 (SR + LO recoil + 2 turns of Sandstorm).
The biggest problems with Cradily I've found are 1) Haze Milotic, 2) requiring Hippopostas and 3) other weather teams. I'm currently using Toxic Spikes to deal with Haze Milotic and so far it's working reasonably well. Besides, even unboosted Cradily actually does decent damage on Milotic, so Milotic is often forced to heal and leave Cradily's switch-in unscathed. There's nothing that can be done about the second problem, unfortunately. Hippopostas is near dead-weight most of the time, although it does have its uses (aka. absorbing Trick). It also conveniently manages to let Omastar / Cloyster set up at least 2 layers of Spikes, etc. It's a bad weakness, probably the most important one. As for the third problem, PK Gaming beat me once with it. He showed me 3 Pokemon that didn't use weather, convincing me that I didn't need Hippopostas to reset weather, and then promptly revealed a SunnyBeamer that wiped the floor with the rest of my team. Once again nothing can be done about this weakness, other than having some prior knowledge of the other team.
I increasingly think Cradily in sandstorm is worthy of the defensive characteristic. Question then really is if the cost of getting the sandstorm there in the first place outweighs the benefits from Cradily's giant defenses in one. In the meantime, I'll keep playing with sand teams.
PS: council still not done? @_@?