They made the best, most well-balanced game ever. Not to mention Casual is pretty good and encourages people to care about winning (even if it takes using a heavy-medic combo, which is a perfectly acceptable strategy), and they made pyro a really well-done class, despite his damage output being rather high. But sill, his damage hitboxes are better, and I have to give the tf2 team kudos for that. Also, I admire how well they reworked the contract system so that you can complete them on your own terms. And they're doing a great job taking their time with comp mode, and allowing alternatives like PugChamp and FACEIT™ to thrive while they work out one of the most difficult conundrums facing TF2 nowadays. Even if their updates are kinda messed up at first, they take time out of their day to fix them all promptly as soon as they're discovered.

ps if you're a part of the tf team and you're reading this, i love you and would jump in front of a car to save your life.