Limits:
PS: 175 (Excellent)
SS: 150 (Good)
PT: 165 (Very Good)
ST: 160 (Very Good)
BSR: 355 (Excellent)
Okay, here we go. I want CAP 2 to have an offensive presence, but I understand the things we have to deal with in Sketch as an offensive boosting move and/or coverage move. BW is a powerful metagame, and if we were doing this concept in DPP I'd likely reduce these limits, but in BW you need to be strong to survive in OU.
Firstly, I want to note that many posts in this thread have convinced me that SS should be lower than PS. The simple fact of the matter is that special sweepers have Hidden Power in their arsenal for added coverage, and have the absolute best boosting moves in the game between Quiver Dance and Tail Glow. Yes, there is Shift Gear for physical, but I think among Quiver Dance and Tail Glow and Hidden Power, there's a lot more to worry about specially. For that reason, I've set SS and PS where they are, with SS being lower than PS. I know this opens up the question of "Shift Gear", but you need to remember that Grass / Ghost STAB coverage is fairly poor, as it is singularly resisted by Steel-types. Furthermore, physical sets lack the versatility that is Hidden Power with which to run a Fire-type or Ground-type move. In this way, I don't think we have much of an issue with these limits.
For the tankiness, you may look at the limits and tell me that "it won't be THAT bulky with just those limits!" but there's more to it than that. Grass / Ghost has a ton of effective bulk in its typing, and you also have to consider just how bulky some Pokemon in OU are. Scrafty, for instance, has 154/154 PT/ST. Dragonite has 157/164. Having these limits easily allows us to be very bulky in addition to our typing, and matches the bulky offense model very adequately. In comparison, Gyarados also has 135/169 PT/ST before Intimidate, but lacks the impressive boosting options like Coil or Quiver Dance. In this vein, I do not think we should be as effectively bulky as Gyarados (you need to remember Intimidate on Gyarados), and so I wanted the limits to be lower than his effective limits. And then, as to why PT is higher than ST, it's mostly because of the presence of such a powerful boosting move to be Sketched as Quiver Dance. When choosing between Quiver Dance and Tail Glow, it really comes down to the Speed boosting and the SpD boosting. I think Quiver Dance can patch a slightly lower ST, but there's nothing equivalent physically. Coil is about the best it's got, and while it's good, it's not boosting Speed, which opens up another can of worms for taking hits.
Lastly, the combination of legitimately high PS and Sketch enables the use of off-the-bat power sets, which may enable us to use more Sketch options like Sacred Fire or some such. Since in those cases, we aren't Sketching boosting moves, we would need a high power for them to be even remotely valid as sets. Hopefully these limits serve us well.
Thanks for your patience and contributions; expect the next stage shortly.