So obviously there's a problem with users in a lobby which for example is needing an engi. The players will join as engi with no intention of actually playing the class, then hoping that the spy for example, does not ready up, and then taking that spot for themselves. Leaving engi STILL open and all the players in the lobby let down because they thought the match was going to start.
My solution: Once you have joined as a class, you would be completely unable to switch to any other class for that lobby!
So basically, if you joined as engi, no matter if you left the lobby and returned, you would not be able to switch to any other class for that lobby. This would solve the problem mentioned above.
Issues (that I can think of):
Miss-clicks [accidentally click on a class that you didnt mean to.] Well too bad. Pay more attention next time.
Changing your mind [I dont want to play that class anymore] Again, sucks for you.
I beleive that this is a serious issue, especially in HL, which I play. Its really really frustrating and implementing a simple feature like this should be able to prevent it!
Let me know what you guys think, and maybe it can be added!