Starting with what I dislike: collectibles (or pickup upgrades). They spread these out over the levels and I find myself scouring the map to see if i didn't miss anything. It ruins the pacing of the game. Some examples of my recent plays that do this are the Last of Us games and the Mass Effect trilogy. If the game is build around exploring your surroundings, it's a different story of course.

What I really like in games is character building and i love it when a character improves depending on your playstyle. A very solid example is Skyrim's leveling system. It just feels more organic.