I am prolly not the best person to say this out loud, but easily, if there was less hostility between TF2 communities, that'd be an amazing start. there's a lot of elitism against half-comp places like /r/truetf2, and while I guess one could simply say "well THEY'RE BAD AND DUMB", that's about 12k potential new people to interact with that you're alienating.
also, less hostility towards specific HL classes in general. as horribly designed as someone like pyro is, you do kind of need one of them, and there's a clear group of skilled pyro players, that could switch whenever they wanted. good players can simply use "lazy" classes, after all. or did we all forget Ma3la used to main HL heavy?