Hey guys just wanted some tips before I make my new take on my old character. I'm not happy with how he became an assassin instead of a thief. So, aside from the usual (eat, sleep, walk everywhere), what are some things to keep in mind to make my Dark Elf a better rogue/thief?

Maybe he could feel he lacked faith, so set himself to be tested by the four corners of the http://www.uesp.net/wiki/Lore:House_of_Troubles. Having done the work required by these daemons, he could have exorcised the limits of the evil side of his nature by taking them to the extreme, and so purged, settled into a more 'middle way' mode of living.
Would he perhaps still hold to the original message of the Temple, to help the poor and needy? Steal from those who can afford it, but always give to beggars and the like.

hmmm, i want to say something like only steal what you use? but that might not be practical.

if you RP eating food or anything it all you could rob Inn's and shop stalls. maybe use the cities as your source of income rather then dungeons? pickpocketing people for your gold and what not.

and remember, your a thief, not a member of the dark brotherhood, so dont kill any of your marks.

the only problem i see with this is those darn random thugs, even if you pull off a perfect theft you find yourself being assaulted by thugs. . .but if you want to add insult to injury. . .rob them and sneak away too