There are some stereotypes about local accents but in cities accents are almost lost. Maybe there are some in far countryside, I am not sure. It's tricky to find Russian native speaker with an expressed local accent.

As for Ukrainian г in Russian speach, I've noticed a funny phenomenon: it switches on and off randomly with no evident reason (I mean in Ukraine, where I live). I caught myself doing that and was surprized. And nobody really feel the difference as I understand.