It depends on what you're doing man. With raids, it's best to hit the lvl cap. It's not required. But people will be more likely to choose you in a fireteam, and you'll deal with enemies a bit easier. In crucible, the Iron Banner is the only thing where player lvl makes a difference. It's not much, but it's somewhat noticeable after a little while. If those two things don't mean much to you, then don't bother lvling up high. I always stay right below the lvl cap. I don't have to deal with armor I worked hard for becoming obsolete and all that jazz you see people complaining about. Everyone calls vendor gear users, "scrubs" but we're playing smarter than raiders TBH. Unless Bungie changes this situation when it comes to the HoW DLC. I prefer staying one lvl below the lvl cap and try to enjoy other thing within the game (which isn't a lot) it makes it feel like the game is less of a chore/grind to play. More people take this route honestly. Hitting a lvl cap within Destiny is nothing more than a small personal achievement/status symbol type of thing.