This is something I've been wanting in SWTOR for a while. It'd be great if we could have more than one spec at a time. I think it could work like this: I'm level 75, and I can put in any amount of levels into however many disciplines I want as long as I don't go over 75. I'd I'm only level 40, I can only put 40 levels into the disciplines, and so on. Say I put 10 levels into Carnage to get Gore, and a few into Annihilation to get bleeds, and the rest into Fury. This would open up a lot more customization for players who want more varied abilities, without making entirely new disciplines. It also allows players to combine aspects of disciplines without making them too overpowered.