I think you really can't go wrong with the better subs, from any of the usual culprits (Hsu, SVS, Monolith, Rythmik, Power Sound Audio, and some others)....it's a value difference I'd think about primarily. The SVS customer service package is a very good one, particularly if you change your mind after an in-home trial. Sub integration can get a bit involved, and it's not about a particular sub really, more just subs in general. Some avrs have relatively good sub setup as part of a setup routine. For tower speakers, the JBL 590 if still on sale for $400 each is what I'd recommend (own them myself)....but check aesthetics first, they're a bit "different" altho still just typical speaker coffin boxes in general....
ps But the 590s are a bit top heavy seeing your dog thing....but there are ways to cope with that somewhat too.