Im a level 45 Breton. I have finished the Main Quest, Imperial Legion, Thieves Guild, Dark Brotherhood, College of Winterhold, and Companions quest lines. Im married to Aela. I own 2 houses (whiterun and windhelm) and i'm always looking for more things to do and places to explore. I have never been bored of this game, and i don't think i ever will. I am just searching for ideas to do later. So far, i'm thinking of finding all of the dragon priest masks (8 i think, i have 2 so far), becoming thane of every city, bard's college, "hunting" every thalmor in skyrim, but i want ideas to do later. I'm always "exploring" so don't tell me that. I'm just asking for what everyone else likes to do.
I guess do the blood on ice quest, its a fun one. Have you done the forsworn quest in markarth? Get all of the deadric artifacts? Dragon priest masks? There is a lot to do in skyrim.. you could always try roleplaying.