I carry the following...
Drivers
Champion Firebird
Champion Teebird
Champion Sidewinder
Champion Roadrunner
Mids
DX Roc
DX Gator
Putters
Pro-D Challenger
I know it's minimalistic, and I'd like to keep it in that vein, but what could I benefit from?
If minimalism is your thing (it's definitely mine), you should pick either the SW or the Roadrunner...those are very similar in flight.
Depending on the condition of your Rocs and Gators, I could see those overlapping a bit too. I used to carry Rocs and Sentinels (the latter being for strong headwinds and shots where I wanted a stronger low-speed fade), but I eventually found a few Rocs that were beefy and overstable, so I dropped the Sentinels completely.
Personally, I like carrying as few molds and as few discs as possible (my bag consistst of TB, FB, Roc, Wizard, and a few very beat Eagles for rollers)...when I was carrying an overstuffed bag, I always hated trying to decide between discs that were very similar. Also, I believe that disc minimalism forces you to learn to become more proficient...instead of using disc X for this shot, and disc Y for a similar one, you learn to use 1 disc for both.
Minimal clutter in the bag = minimal clutter in the mind