Welcome back!
I've got a Tartarus/Naga combo too. You don't need nearly all of those hot-bars.
I have 1-10 bound to the tartarus keypad's first two rows as well as tab, f5, W, f6 and f7 on the top row.
W of course makes driving/running simpler, and I can steer with the thumb stick.
I can still move using the mouse, but I've found my hand cramps from gripping the mouse too tightly.
The center mouse buttons are bound to Ctrl and Alt.
So the second bar starts with Ctrl+Tab (usually a CC ability) then Ctrl+2 through Ctrl+10.
I leave Ctrl+1 as companion attack command for simplicity.
The 11th and 12th spots on each bar are bound to the F5 and F6.
On my scoundrel/agents they are used for stealth and neural dart.
I've found healers with a tank companion to be the most forgiving in solo mode.
If I can be any help, please feel free to inbox me.