Don't know if I said it in the PM, but you can keep the GSC movepools only (instead of GSC/BW) if you insist on it. Submission, for example, comes back into play, which is a little more helpful for Blissey, Snorlax, and Tyranitar (no one gets it now).
For the most part, moves weren't modded to work like GSC. Spikes can be set in layers, Explosion/Selfdestruct is weak, Mean Look can't be passed, etc.
Also, forgot to mention that we played with Natures and EVs on. Found the customization in that much more enjoyable than static values.