Medal of Honor

I suppose that this game was made for hardcore players, and I wouldn't know how it suits mediocre players, because I haven't been one for long. Despite, my experience and skills acquired I doubt that a beginner would be frustrated by the game, because the game requires minimal experience. You don't have to learn how to counter the recoil, because it's non existent. It doesn't require that you play for ages to unlock all weapons or perks-that aren't necessarily universally beneficial-, there're few to unlock to anyways. What this game emphasizes on is choices that you and your team mates make. The maps are big enough to always provide alternative route to destination, but are small enough that you have to make right choices to survive (a.i. turning around wrong corner.) The game requires that you analyze (through position of friendlies, and general knowledge of spawn of enemies) the likelihood of certain path being free of campers, and allows you to mount kill-streaks if you choose the right path. It's also adrenaline rich, because killing or getting killed is quick so you have to have top reaction and determination to kill- no shooter skills or long history of playing the game previously.

This game was truly designed with advise of tier 1 operators, as they shared their tactical knowledge, hence letting designers implement surroundings that would require their mindset to succeed.