For real altered v7 extensions try the old standby; come into the chord from a half step up and you're sure to get some attention! Not to mention hitting every alteration known to man!
Now for playing the harmonic minor as a substitution over a fairly normal minor 7th it's always tastier to build up to it by perhaps first using the run of the mill minor scales then switching to the true melodic minor with the different decension finally tearing off the h/m at full throttle and bending that last interval! :)
