There is very little difference between most all the SIG's, size wise. If the 226 is a brick, so's the 229, and actually, the 229 is a little fatter than the 226.
The 226 or 220 are really no bigger than a Colt Commander, if thats any help.
I'd suggest finding a SIG dealer and get one of each in your hands and see what feels the best to you. I find the 226 feels just a tad better in the grip, but 229 seems to point better for me.