(Yes, yes, I know. This one runs well past 200 words. But I didn't want to dedicate another day to TF2 and I wanted to complete my thoughts.)
...are just right – challenges of moderate difficultly that can be completed by playing the class well, without deliberate steps taken just to earn an achievement.
I’d say this first experiment with class achievements and unlockable weapons was a success, but there are a few things I would fix for the next round of achievements.
* Release achievements packs for more than one class per update, preferably for two wildly different classes so teams keep a modicum of balance. Examples: Scout/Engineer, Spy/Pyro, Heavy/Sniper, etc.
* I don’t know if this would work, but make some of each class’s achievements achievable by all classes, so servers aren’t spammed with just the latest class to get an achievement pack. Take the Medic achievements. Achievements that require you to work with another class should have been rewarded to both the medic and their medic buddy. Also an achievement or two for all classes attacking a medic would have been nice, like an achievement for killing a medic right before he activates his ubercharge, or for killing a Medic and his Medic buddy within five or ten seconds of each other. That would have kept servers a little more balanced those first couple of days after the update when servers were spammed with dozens of medics.
* Discontinue achievements that require players to use the Steam or Xbox Live friends network to join a friend’s game to complete an achievement. I’m particularly jaded about this one, after getting spammed again and again with friends requests by complete strangers just wanting to get the “With Friends Like these…” achievement on Live. Call me an antisocial shut-in, but I don’t want to befriend complete strangers online. I want to earn achievements just by logging onto a server and playing the damn game, without worrying if someone else is online.