Yeaaaaaaah, portable anti-grav packs! I cannot think of a single situation where those WOULDN'T be appropriate. Not one. It'd be a far goal, but this can easily be fixed onto a vehicle for going over water in the meantime...

[You know... he owes her one for coaxing him out with that bouncy slime all over. Something clicked in his head back there, that he's sure would have taken months otherwise. He smiles and gestures to the repulsor field.] Hey. You want to try it out? I'll be right here, so nothing'll happen to you; Just watch your feet when you land on the other side.