Pioneer VSX-832 is 5.1 capable, you can buy a center channel speaker to improve dialogs.
HomeTheater
Sound-wise, I think you will not see a huge improvement. Are you able to go to a store near you to test the soundbar?
Realistically probably not. I think the only place around here that carries the ones I'm interested in is Best Buy, and I don't think testing something in a Best Buy would give me much insight to how it would sound in my house. :( I'm looking at like $800-1200 stuff and the local fancy home theater place mostly carries $2000 stuff.
I never bought anything from Best Buy but I visited one near me to preview a few speakers that I eventually bought from accessories4less for my 5.1 setup. I was using a soundbar for years before that and I’ll never go back. Just my recommendation based on my experience. I have a 2.0 setup also that I just upgrade my AVR for and am very happy with it.