Suggestion to make highlander lobbies fill faster

Have been playing lobbies on this website for a couple of weeks now and noticed that there is often a problem with finding medic, engi and heavy. I'd suggest implementing a system, which will require every expirienced player to play those classes once in a while. For example, every player with at least 50 lobbies and at least 500 hours will have to play medic/engi once in ten games and play heavy once in ten games.
Something like this will be useful simply because us, players, will spend more time playing and less time waiting. There are indeed couple of flaws for instance people creating a lot of alternative accounts because they simply don't like being restricted to play the class they dont want, but I think those problems could be solved by making a restriction less harsh.