One of my favorite shooters of all time has to be Halo: Reach. I played a few games of multiplayer recently, after months of playing other shooters and games. I used to love the heck out of Halo: Reach, but after coming back to it and seeing how foreign and odd the controls are compared to other games made me think a lot.
Honestly, I got used to Halo: Reach and it's quirky controls when I first started it. I used green thumb cause R3 or whatever it's called felt so much more natural to melee. Although, even though it felt natural, the button for scoping was mapped to RB and was extremely weird. Since I was trying to platinum TLoU before playing Reach, I had a desire to constantly crouch, but that was mapped to the right stick instead of B. It was just so confusing to play, and the only thing that stayed universal was using left stick to move. Although both of these games are extremely good and fun to play and I enjoy the single fire guns, the controls are so quirky for a beginner to video games. Then again, I don't believe there should be some universal button mapping for shooters either.
I'd hate to say it, but this is kind of why Call of Duty is so easy to pick up and play. The controls aren't quirky at all, and almost everything just feels natural. Even the killstreaks are mapped to the D-pad so they don't really interfere with any other buttons. There aren't any armor abilities or menus to sort through while playing either, besides killstreaks. They even mapped the trigger on the PS3 to R1, unlike Rockstar's LA Noire, which uses that godforsaken R2. I'm in no way saying that CoD is a good game for doing this, I'm just saying they make it extremely simple. I do prefer the PS3's R1 over the 360's RT for shooting since it's much easier to press and tap, so you can start shooting much faster, but that's my opinion and a whole other conversation. read