I would suggest you look into a more affordable set of components and do 2 sets of them for your front stage...
use your 4 channel the simple way instead of getting crazy with bi-amping.
Memphis makes their MSQ components....for the money they are a great sounding set of components. Tweeter is dock able (point source) or separate able.
You may also consider doing 5 1/4s for your kicks as well...smaller even still and they reproduce male and female vocal ranges much better...which have the similar tonal qualities of House, Trance, Bass CD Voice Narrator sounds/frequencies that make that music much richer and cooler. (add electronica voice sounds here) lol
This way you could use your whole 4 channel to run your front stage, not "dirty" the sound quality by raising the THD from the amp by increasing your load to 3 or 2 ohms when bridging/ or paralleling your speakers.
When doing this minor change in configuration you have more cone mass, more clean power, less chance of distortion at higher volumes, and something you can not recreate with one set of components.
Along with sound deadening, very sealed mounting baffles and fully separated front and rear waves, among other speaker tweaker topics....that would all be a good start.
How about a 4 channel line driver?
This could go on and on...