Hit level 18.5 yesterday and its pretty fun. I just joined the thieves guild, although I can't sneak or pickpocket, I am pretty decent at lockpicking though.
Kind of feeling lost in this game though. I expected the quests to come to me really, but I have to actively search out for quests and questlines.
I know everyone says to not fast travel because you miss out on things, but when I'm at one side of the map and it sends me to the other side of the map, I'm not going to blow 45 minutes of real time (or more with fights), to get to the other side.
I upgraded my armor at the workbench and also my axe and i'm a lean mean, killing machine. Still can't kill Giants as they take me out with a couple hits, but I'm hoping that will change once I get to 100 crafting and can make the dragon armor.