I’m all for Donald and Douglas, and probably Devious Diesel too. Also, some other suggestions:
Bill/Ben
Harvey
Oliver
Toad
Stepheny (or however you spell his name)
More rolling stock (maybe with removable loads)
Breakdown Crane
Duck
Old Coach (From the Cranky Bugs video/DVD)
and Diesel 10 (claw opens/closes when he moves)
Oh, and maybe interchangeable faces like mad, worried, sad, and stuff like that

~Styntwin409 (formerly Justin, but I doubt any of you remember me)

I think it would be wicked cool if someone made Henry in his blue version from the old stories.

~Styntwin409
P.S. Anyone got any Thomas & Friends projects that are quite easy that they can tell me how to do, or at least what things from Sodor are easy to model. Thanks!)

Wow nice job! I really like the coach that you made. Keep up the good work!

~Styntwin409 (formerly Justin, but I doubt anyone remembers me! =])