I only play vanilla demo, since I was demoknight, then I got tired of it, and traded all my stuff away. Since I had a gifted hat for demo, which is one of my favorites by the way (Scotch Bonnet), I just decided to go vanilla demo. I mainly use the sticky bombs as my main source of attack, but in cases when enemies are behind a corner or through a doorway, I'll use the grenade launcher. For medic, I usually stay at a choke point and give out heals and move up with everyone else. As for soldier, I'll rocket jump around and take them out with my whip, but mainly rocket launcher for long range. Pyro is just a degreaser axtinguisher combo. I don't play the other classes as much, but I do from time to time.
Also, F2P medics are horrid. I had 18 health and a medic was staring at me healing a heavy with full health.