^^ Grim Dawn? ^^
Depends what your looking for EXACTLY.
Marvel is very fun and F2P, just super grindy. I still play it quite a bit and am almost maxed my goal grinds out. You can spend money to unlock heroes/costumes/pets/etc, but you can also grind for most of it too. Always fun playing a super hero, but its hard for them to balance 50+ heroes. Some of your favorites might be underwhelming....
Borderlands games are GREAT. Fun stories, lotsa loot, great characters. Just dont expect to be end game and kill Raid bosses, but you will get hours of fun from each one of them. Just have to shell out money for each game and all it's expacs.
Never played the Helsing games, allthough they are like D2 or D3 meets Vampire/Werewolf world from what I have seen. They are on my list, just never gotten around to it.
Grim Dawn is ALWAYS being added to, and is a pretty solid D2 clone type game meets Titan Quest. I enjoyed the game,. and enjoy going back from time to time.
Not many GOOD action RPG's out with guns and stuff, depending on what exactly you want or call a gun