It's obvious from the Dev's socials that Alice is the main face of the game, but honestly I find Hanabi's routes to be the hottest.
In the sadism route she just escalates without stop. She didn't have fully established sadism prior to meeting the MC unlike the other characters (her first meeting she's shrinking some delinquents, but doesn't yet seem to enjoy like with the MC later), so in a way you are responsible for corrupting her to be like this. She's even super happy to see you return to her the first couple of times, like a twisted romantic relationship.
And the motherhood route? Super hot, and for an added bonus you get to experience all the other bad ends before sending the MC running off to beg her for help. Didn't get to see her with large breasts like the image earlier in this chat. I assume that will show up in the next update?
Either way, looking forward to seeing the end product soon (assuming they keep to the release this month's end).
Edit: Incidentally, is there a way to legitimately beat Alice the first time around? I can beat her in the second attempt by asking her to go easy, but given that the other two enemies (Hanabi and the fungus futa) can be beat with careful planning, I wanted to see if there was an option for Alice too. I know you don't get any scenes for doing so, but I wanted to do it to satisfy my completionist tendencies.