I just recently bought a shit ton of beta alanine (thank you Jered), and it's a product I love. I also got a sample of agmatine sulfate which feels like the feel good ingredient in Jack3d. I hear good things about Alpha GPC. Caffeine is a give as is Creatine HCI.
So I'm thinking of making my own pre work out mix that looks something like this

300mg Caffeine, 1000mg Agmatine Sulfate, 1000mg Alpha GPC, 4mg Creatine HCI, and possible Huperzine A dose to be determined. And I'm reading up on flavoring right now.

Thoughts? Additional ingredients (I'm thinking grape seed and celery extracts).