ways to fix pyro:
3) Make the reserve shooter for soldier only. There really isn't a way to change it to make it less op without completely changing the entire weapon. Maybe Valve could make a special reserve shooter type weapon for the pyro only.
5) Change the flare gun so it mini-crits people who are on fire instead of doing a full crit.
6) Change the axtinguisher so it either does mini-crits or swings slower(not slower attack speed but the time it takes to do the initial hit is reduced)
They should make a "Reserve Shooter" type weapon for the pyro that only mini-crits those who are Airblast-stunned (or just stunned, if its easier) or just enemies who are still in the air from being airblasted.
They can balance flare guns by giving it a 1 flare clip with 16 extra, instead of just 16 flare clip. This should stop speed flares.
The fact that the axtinguisher has no random crits should be a good enough. Sure, it can suck, but its only a 1v1 thing usually. Its a specialty thing, like the market gardener for the soldier (though i will agree that market gardening is much harder, but thats beside the point)
In honestly, they just need to reduce the speed of the pyro.
He has the 4th highest health, and for the amount he has, he is way too fast. Even if its a minor speed drop like the demoman, it would balance him out.