Originally posted by Xmas 28mm /2.8 are more plentiful and cheaper than 35mms
There's a lot of optically inferior 3rd party 28's and 35's. When you get out of the really weak performing stuff the prices start to become more comparable.
28 on full frame seems kind of wide for a sole lens. A 35mm would be more useful for subject framing, I think. A 35, a fast 50ish, and the OP would be well on his way. On full frame I don't see a reason to go with a 28 instead of a 24.
My 2 cents, worth maybe half as much.