For a while now I've been playing a version of Fantunes that's modified for ACBL GCC, as follows: - 1C must be 15+ (and 2C therefore is 11-14) - Since 1N cannot include 4441, we open 1D unless the singleton is in diamonds. With the 4=4=1=4 we have to open 1H. (After a 2-level response, we play that 2N by opener shows the minimum 4441 with singleton in partner's suit) and is NF. - 1M-2C non-GF is not permitted on less than three clubs, so we have to bid 2D on balanced or major suit raise hands with fewer than 3 clubs and at least 3 diamonds (and we use 1M-3N to cover GF raises without three in either minor). 1M-2D isn't a very comfortable auction as a result, but we manage. Also their 1D-2D on a weak reverse-flannery shape isn't allowed, but that isn't really that important to the system as a whole.