That's what Brother None said:
''As for the PC being not very distinctive compared to TNO, this was a decision made very early on by the core creative team, reflecting the character's role in the narrative much like TNO's very distinct look reflects his.''
Probably it's just an excuse :D
Well I made me complaint known when I made that thread about distinctive protagonists as Biggrin over on Torment forums, an got an answer, so I suppose just gotta wait an see if this is actually used in game an mechanically reinforced. I still say you could make a better lookin an more distinctive main character than what we got now, an I suppose you could argue that, but proof o pudding is in eating at end o day.
Don't know why the devs'd wanna make protagonist most boring thing in an interestin settin, sounds fucking stupid to me, but they could pull it off I suppose if reasons good enough. Hope its not just an excuse.
^Fuck me Thief were good wi them Hammer bits weren't it?