Although the renders are nice, FILF has many games like it. If you have played Sisterly Lust, Milfy City, Big Brother, or Man of the House... Guess what! You also played FILF. It's the exact same story in all of these games...
Altered Destiny though... You literally get a time machine! You can go back and forth changing the past and present. It has so much potential. You are dealing with multiple timelines here and you can go back and forth changing so much stuff. There is "Timestamps Unconditional Love" too which is of similar genre, but at least it's not a story that has been beaten to death as the previously mentioned one in FILF and a hundred other games. This has the potential for all sorts of crazy shenanigans.
The basic setup can be the most cliched out there, whether it's going to be good or not, falls upon the ability and the capability of the story writer, not the scenario itself. You could create the backbone of a story from the most generic elements, and make it into something outstanding if you're good enough, while you could have the most unique backbone, if you're incapable of writing a good story around it, it will end up badly. If you strip down AD and Filf, both has the identical elements to it, with a very generic setup. Single 20ish guy lives with his mother and sister, and has a bunch of other girls that he can meet and fuck aside from them. AD having the time travel element to it doesn't make it automatically better.
If you feel Filf as a very generic game, that's because ICC made it into that, and no matter what extra unique element he uses with AD, it could end up with the same result. Actually it already did in many aspects. Ultimately it's always about how the creator uses a tool, not the tool itself. Given how linear both games are and how similar the writing style, the time travel aspect won't be able to make that much of a difference and shoot this up who knows what heights in any regards.
If you take this into account, the question of which game development should be prioritized if they will end up similarly anyway, is very simple. The one that managed to pull in a crowd around it, and with all it's genericity, managed to become somewhat successful, not the one that already caused a massive shitstorm because of a very badly written plot element in it's very early stages.
