Sadly this is a wrong question. It really boils down to what fetishes you are into and what level of completion of a game lead to a satisfying playthrough. Some would like an unfinished VN or long game where you would like to know what the developper had in mind, some would like it extreme, some would like it romantic.
All in all, it is those game which are quite varied which would please most of people and if the dev(s) is/are very active it would put pressure to completion. Often, we do not know how many days of work were already spent before the first release and often a fast rising game would be abandonned, since the dev(s) would not be able to keep up with the community.
If potential means viral/popular and recent and unfinished, it is just the fav of the month, which leads to nothing really since the best games just take time to develop.