The -10/-11 differences aren't any worse than some other common TRs out there. The 75/76 has wayyy more systems/equipment differences and they fly a little different too.

A340 and A330/A320/A319 are all common. Pilots at some airlines fly both the 340 & 330 just like we fly the -10 & -11 (and one of theirs has 2 more engines than the other).