I've been playing a good bit lately and my experience has been similar to yours I think. I rolled one build that I had a really tough time with, tried another with the first one's mistakes in mind and am soloing everything so far.
It's probably the most fun I've had in a run and gun for ages. I've joined quite a few co-op games and that's some fast paced, pretty brutal fun too.
I'm only up to
(is there a better name for it?) so far, so I'll wait before tackling the new free dlc area.