if a room is lively already, horns might not be a good idea ( not saying it cant be done ), but maybe a speaker that is a little bit on the warm side would be a better choice.
Why not horns?
I've owned a lot of speakers over the years but I have never experienced anything like the midrange reproduction from my horns. With a frequency response of 300 Hz. up to 14 Khz. from a single distortionless driver, it seems like a no-brainer that everyone would want this performance. Why don't you use horns?