They should make the phlog's airblast delete projectiles like the SC
Interesting idea here based off of what you said. A flamethrower that is very meh damage wise, but allows you to suck up a projectile (at 25 ammo per projectile and 5 ammo per "tick") and when you right click again said projectile comes back out of the Flamethower for 25 more ammo. The catch is it counts as regular damage instead of a mini crit and does not retain crits when they are sucked up but can still deal them in cases like a headshot with a huntsman arrow or a flare on a burning enemy.
It'd be interesting sucking up a rocket, and shotgunning a Soldier to death and use the rocket to say bring down a Sentry or get you out of a tough spot. It would have some sort of indicator that the Pyro is holding something however when the Flamethrower is out, so it's not some huge surprise when it happens, this also wouldn't work with sticky bombs of any sort. (Also imagine sucking up a sandman ball or an arrow!)
Edit: Thinking about it however, something like this should come with some sort of slight passive health/damage or speed penalty to remain fair.