I understand where you are coming, and have felt the same sort of pressures myself. However, in the case of tournaments, I think it is up to the individual to manage their own game load. In entering a tournament, the player knows how many games are being committed to (with the possible exception of the yearly site tournament). I see it as a responsiblity to play those games (or, yes, resign them).
I agree it could be a good feature to be able to set a maximum number of clan games, however. Clan games are the one area in which the individual relinquishes their control over their own game load, and I think it would be nice to return some degree of control to the player. A clan game load limit would essentially be an automated toggling of the clan availablity option, depending on a set number of games a player is willing to accept for a given clan.
The only alternative at present is to leave clan play entirely, which is what I have now done, or to pay very close attention and manually toggle the clan availability, which is what I had been doing and got tired of!