I don't know about Spy because I don't play him, and the maps I've really enjoyed, I think that's a subjective thing. As for Pyro, he's been given the shaft since day 1 and his flamethrower was always inconsistent which they finally fixed after 10 years. They also changed Pyro's afterburn, you can't just puff and run anymore, the time afterburn lasts depends on how long you hold the flamethrower on the enemy for. As for his new weapons, the only one that I can kind of see as annoying is the Dragon's Fury which is basically a bigger and more powerful flare gun.
Also the new contract system is really good. You can choose what contracts to unlock, but you are still rewarded with locked cases, but you get war paint instead of weapon skins. And tiered cosmetic crates as well. Pyro's weapons you can obtain for free, with his contracts, which don't require a paid pass.