Is it possible to play a smooth talking sneaky thief type character who can talk his way out of situations or find clever ways around? I was considering this for my second character (months from now...) and wondered if speechcraft really opened up THAT many new options to handle situations. I know I'll have to fight some too, but wondering how deep the speechcraft side of the game was. Thanks.

It doesn't really allow for any new options. You have the same options (persuade, intimidate, bribe) except they have a higher chance of being succesful, and almost all of the time, if you have the perks that increase these options, they will work. Along with that you can get better deals and more gold for merchants, but that's all.