I agree that the perspective of the characters doesn't work/match the one used on the background. You should either do what gil said about vertically "compressing" the tiles, applying foreshortening on them, or doing that to the characters themselves.
I did an edit on the character, look at the dudes on the right. Two versions with foreshortening, the left one is with some, but i felt it needed more to fit the background, so i did the right one. You'd leave the floor tiles intact but apply this same technique to the wall tiles.

Edit: nice, just noticed i repeated Terley's post. Nhoh.
Your edit doesn't really show like terleys

. They look like midgets.. but i get what you were trying to show, thanks. Anyway i don't really like that perspective, i rather have the chars and tiles not match.. after all, it doesn't matter.. Look at Zelda.
Anyway Gil, FF isn't iso.. you obviously don't know what iso is.. so yea.. Anyway thanks everyone

. Ill fix the worms somehow, they were made pretty fast.. Next edit will contain some new tiles, make sure to check back when i edit my post.. in a while
