I've got a Naga and i play a Sentinel as well,
The best way to set up the Naga, for me, was to switch your naga to (NUM) on the bottom of the mouse. Then you will have to "Rebind" 1-12 (Probably already have done this though)
Next what i did, because 1-6 is really easy to reach, i bound Shift 1-6, then CTR 1-6.
I kinda had all situational abilities on Shift 1-6, (sft 1 twin saber throw, sft 2 pacify, sft 3 interrupt, sft 4 inspiration, sft 5 transcendence, ect) and Defensive Cool-downs on CTR 1-6 like (ctr 1 = Guarded, ctr 2 rebuke, ctrl 3 med pack, ctr 4 warzone defense thingy, ctrl 6 is huttball throw) and of course my main rotation abilities are on "single" key binds.
Now whats different for me is i use a Gaming pad, Belkin n52te,( not the best for mmos if you have a lot of abilities) but im soo used to it so i cant switch back to the keyboard. so i don't use "1-6" on the regular keyboard.