Oh course he's not invincible. I'm not saying he's perfect just that he's OP compared to the other raiders that are relatively balanced. It's an unwritten rule in game design that a fast character cannot also be strong and tough, or that a healer cannot do massive aoe damage, ect.
That holds true for other characters. Alicia can do massive damage but only has a short range, Harek is a glass cannon. Valeria is a power house at crowd control but only after a set up, she is slow and her gun alone doesn't do much damage.
Yeah Hans is extremely well rounded but he's not one shotting ppl. Rak can do nearly everything but snipe with seemingly no drawback. I got no problem with the players and posters. The game is horribly unbalanced at this point and knowing that we're going to have to wait till they implement a new mode for them to work on these problems is incredibly frustrating.
Put out the fire in the room before you start building new furniture.