I would second the Cary suggestion, or perhaps at a slightly lower price point you might consider a Conrad Johnson CAV50, which should sound wonderful with the ProAc's. I've never heard the Rogue, but everything I've read about it so far it has been good. The only caveat I'd have with the AR suggestion is that while its a very good quality integrated amp, it doesn't provide a particularly warm sound, which is what you mentioned you prefer. Still, the ProAc/AR sound is well suited so it might be worth considering.
It might be worth noting that all of the suggestions to this point have been tube amps, and probably with good reason. From my limited experience, I've found that there are many solid state amps that will drive the ProAc's well and sound pretty good, but in general ProAc speakers simply sing with tubes. Unless you're averse to the maintenance overhead (and costs) associated with tubes, you might consider leaning in that direction.
