To the best of my knowledge, Jason, MC5 has the best that SI drums has to offer.
I believe it has many patterns that were not included in the original release. I'm open to correction on this.
You can also easily create or modify patterns in the PRV.
Use the SI Drums map to make sure you stay within what SI can play.
Understand that SI was never intended to be particularly elaborate.
You may be looking for more than it can deliver.
SI is GM mapped, so you might be able to download GM patterns that will do what you want.
Personally, I like rolling my own. Give it a try.