Ryan, keep in mind whether you go single driver Cain & Cain or Horn shop, room placement is critical. In a sense you need the room dynamics to assist the single drivers in delivering the full range of music. You mentioned something I thought somewhere about not being able to place the new speakers in the corners of your listening area, well for the C&Cs and HSops that corner placement is important so bear this in mind.
The audio asylum site is full of good ideas as well as these\/\/\/. Should help you spend a month of evenings lurking around.
FullRangeDriver.com
http://melhuish.org/audio/index.htm