I ended up going for the Bryston B-60, and am very satisfied with my decision. In comparison to the Teac A-1D I was previously powering the 5.0s with the Bryston has a significantly lower noise floor, focuses the image better, and has more control of the low end - just to name a few improvements.
My better half was questioning the value of upgrading the amp, so I set up a blind listening test, and she picked the Bryston as the one that sounded better every one of 6 trials. That seemed to convince her haha!
Thanks for all of your suggestions!