Score v2 seems so much better than w/e we have now. Especialy non-farm maps;
v1
-> you play 30 sec map, get 64% acc, miss some slider ends and a few circles at the end -> here, take a huge reward.
-> play 10 minute map, get 95%, but miss once in the middle -> Ehh, you're not worthy
v2 fixes that and introduces more competition on easier maps with slider accuracy, since it's harder to reach a perfect score.
But replacing old system for old maps is imo unfeasable EDIT: not programmically, but due to public out-cry.
One solutions I could think of is letting mappers choose if they want to use old or new system. And, perhaps, after transition period, forcing all new ranked maps use v2 scoring system?
Another solution is leaving it as a mod, and just multiplying v1's SS score by v2's percentage, allowing both systems to coexist.