I've been playing the following structure for a while now: 1C: ART, F1, 17+ bal / 16+ unbal 1D: 14-16 bal OR 11-15 with 0+D, at least 1 4c major, not 5+/5+ minors 1H: 11-15, 5+H 1S: 11-15, 5+S 1NT: 11-13 bal (5cm OK, rarely 5cM) 2C: 11-15, 5+C, no 4c major, no 5cD 2D: 11-15, 5+D, no 4c major, no 5cC 2H: 4-10, 5+H, undisciplined 2S: 4-10, 5+S, undisciplined 2NT: 11-15, 5+C/5+D I think it's been working rather well.