Upgrade Ideas:
Soldiers: Always focus on reload time, max ammo, and possibly clip size. For resistances take critical damage resistance, and bullet/blast depending on which seems to be more prevelant for the round. Movement speed and health regeneration are optional.
Heavy: Always focus on max ammo. Projectile destruction is only useful for demo/soldier spam. Penetration MAY be useful, but I have seen no practical reason for it if the heavy is kritzkrieged. For resistances Blast/bullet/critical. Movement speed may be useful for strafing the enemies. Health Regeneration is also useful, when combined with movement speed you may be able to sidestep most attacks.
Demos: Always focus on reload speed for both weapons. Clip size is useful for the grenade launchers. Previous resistance upgrades are the same as previous classes.
Pyros: Always upgrade max ammo and pushback. Movement speed and health regeneration can prove useful.

On a side note, I just learned that you can improve your class directly, so that may be somewhat useful.

Well, after some planning, I think we can beat it with 4 engis a heavy and a kritz medic.

Ok, so when they fix the whole server issue we need to group up again!

Ya, just did that...going faster but not by much

@ lorn & rox
Try changing your region if yo internetz be fast enough, gotta be somewhere in europe like sweden and must have atleast 15 mbps download rate

steam is being slow on the update :(

Hurry up need more wite wimen

I would if I still had money in my steam wallet

mebe for earwaxbuds