Other comments are jogging my memory. I think we went case sensitive (62 characters -> 30 spares), eliminated aA4, eE3, iI1l oO0 (maybe Q), uU, which is 16 characters, 14 to go. Remove the remaining 7 numbers (once you remove most for leetspeak what's the point of the rest?), nN, yY. That leaves 2 left and I can't recall what we did with those. Maybe kK or rR.

Y is pretty versatile for pissing people off.