OP, your idea isn't horrible, but I do think we're way too early in the game to depend on lack of merits being responsible for someone getting censored or anything like that. You know I'd be all in favor for a goal like you mentioned, but I think this proposal has too many potential pitfalls to work--yet.  Maybe in a year or so if we still have jr members with 600 activity and 23 merit...those folks might deserve to be stealth banned or some such thing. 

Remember, it is in fact pretty hard to get merit points for the vast majority here.  It's really going to take some time for them to rank up--especially if their English sucks and they don't avail themselves of the local boards.