As part of my BC Rich warlock modding project, I am going to do a lot of routing(for floyd rose) and a pickup switch, so i figure i should ask about adding another tone pot maybe even a killswitch and coil tap.

The pickups will both be SD Invaders. Are these humbuckers coil-tappable?
Here is what the body layout is now. One volume, One tone, and a selector.


Would it be possible/practical to add a killswitch and another tone knob and then make the tone knob for each pickup also act like a push/pull coil tap?
Yes. Invaders have 4 wires so they are ready for coil tapping. You can add as many switches and knobs as you want, provided you are willing to drill holes for them, and it seems like you are ready to try anything. Sounds like you want most of a Jimmy Page wiring setup, plus a kill. This will become a fun guitar to mess with!