Have you looked at how movement type 1 works in TftD? Is it "fly everywhere" or just "fly on land"? Either way, I guess it would be nice to have the full set:
0 - Walk everywhere
1 - Fly (on land or everywhere?)
3 - Swim in water
4 - whichever one 1 isn't
Although of all 4, fly and swim is the least important I guess, but it would be good for end game super/iron man type movement that fly everywhere.