Space marine 2 is an epic game, I feel people judge games way too harshly these days if they're not a massive open world rpg. The gameplay is extremely fun and addicting, graphics amazing, story amazing (good enough to make me to purchase 5 warhammer books)..People who say the game is too hard have not developed the skill to play, difficulty levels exist for a reason....The other complaint I see alot is that the ranged weapons aren't powerful enough...The developers want you to use melee weapons equally because thats how the Astartes roll in all the books (and I also disagree, the ranged weapons are balanced and do appropriate damage)
Most negative reviews are overcharged game hating weirdness complaining the games too hard...Don't listen to the bull, buy the game, quit your job, get divorced, play some more.