PC What's your opinion on modders/modding?

If you're going for the good mods, they are basically DLC Content but without having to pay for it. Adding new content and making the game worthy in the long run, or even fixing problems or some bad things that the original game has (SkyUI I'm looking at you). I do play alot of games that has modding features, I don't think they should be something bad. And there's that thing: If the mod is a cheat at SINGLEPLAYER, it's no problem. The player knows the consequences of cheating at singleplayer and losing all his fun. But... If it's a mod on multiplayer that do give some cheating on PvP or something... Then it's ban potential.