Far as I've heard/read I don't think v0.16 will be the last, though it is commented on the patreon site that it's one of the biggest updates and that it was delayed and supossedly should be released at the latest today, unless it get's delayed again.
Should be made clear with the release I suposse. But at the moment I find it hard to believe that the game would be finished with the next update since at the moment the heroines have way different stats Vera 60/30 Sen 65/20 Theo 75/30 Irene 70/20 Elisa 65/20 Rachel 50/3 Uno 65/30. At the moment there are 4 endings Elisa good? ending, Sen bad ending, Uno good? ending and lastly Vera, Theo and Uno harem ending. I put good? endings on Uno and Elisa since their endings actually sad/bad in my mind but the game doesn't mention them as bad while Sen's ending is called a bad ending and it is just that.
My guess is that each character should have at least 1-2 endings on top of that there are several harem combinations, outside of the one above though this might not be correct pairings. So far there is seemingly a lot of combinations since there are scenes with Irene + Elisa, Theo + Elisa, Theo + Irene + Elisa and so on. So probably each of those combinations would need an ending as well.
Anyhow here is a for now 100% save for v.0.15 to use in the next update if anyone wants, it's with all the girls being girlfriends/lovers/fiancee.