In addition to the stats suggested by others -- in particular the idea of a sucking mechanic to absorb projectiles (and players?) the overall Domestic Pyro set is just lovely.

I think a pyro flamethrower that specializes in airblasting, manipulating players' projectiles and positioning could be great.

I can imagine this greatly increasing the pyro's freedom of movement, if you could absorb a rocket and then use that to jump away, even more freedom than the jetpack does right now.

I can imagine a lot of sucking up players just to drop them off the map, or to pull a medic away from their uber target! But it might not have a long range, and it might be cumbersome, so there could be risk-reward there too.

It's amazing that this is from 2012. I'd really like to see the whole set added, but especially the Gutguster.