There are a lot of pro amps out there. Before going that route, you need to be aware of a few things. They are not meant for HTs, but pro apps, so display dimming will often be nonexistent. My own Crown, I have to put solid black tape over the display, as even tint ain't cutting it. I even put tape over the little blue light for "on", as it puts a bright blue square on my screen otherwise. It likely won't have a 12v trigger like consumer amps. Lastly, you will want to know if the preout voltage of your current receiver is good enough for pro amps, and if not, you can use something like a Samson s-Convert. If you do need one, I'll sell mine to you for less than I bought it, and I've used it for about 1 minute or less with my sub.
That said, besides the non-consumer nature of my amp, I do like my Crown XTI2000 that I got for $500. The free band manager software has been nice to play around with in getting my sub's output closer to personal preference, post-Audyssey. I've done maybe 5 or so experimental/guess EQs as for what I might like.
A cool thing about pro amps is that you can use Speakons.
edit: the above all said, I still vote for 3ch of amps if you are really set on getting on outboard amps. Center channel has a lot of material, however, do you use the center channel when out of the room (matrixing stereo)?
