Personal opinion, but nothing felt clunkier than shots being +10 heat back in 4.0. Felt like constant hard stops to prevent OH when you didn't want to, whereas now it feels pretty smooth. I too have my Flamethrower gripes (mostly that being I'm fired of that being made out to be the most amazing thing we got in SB when it just isn't), but I've accepted it for what it is now.

Haven't done much PvE wise lately so I can't really chime in on the rest.