Speaking in my capacity as Some Internet Rando, here are my opinions, for what they are worth. I have played the 1.2.2 version, but not 1.2.3, which fills out the Depravity path a little more.
I agree with the first choice being kind of opaque. Given how incredibly important that choice is to everything, it could (and in my opinion, should) be way clearer that you're choosing between seducing the girls and raping them. Maybe after you click it, it says "here's what this path leads to, are you sure this is what you want" and then you can change your mind or something?
I have no particularly strong opinions one way or the other on "Milly steals girls from others." It's not my thing, but it's not not my thing, you know? For girls being stolen from Milly, how I feel about that depends on the relationship. The worst case scenario is the expected "how dare you, she's mine," but that's not what I expect to be feeling here. I am expecting "pfft, she just happened to be the nearest hole when Milly's lust got out of control, have at it."
The big thing about Ollie and Hana that stuck out to me is the part where he was playing video game so she could watch. He did this with headphones on, so she would not have been able to hear the game. And put on a movie so she wouldn't get bored. At that point, he isn't "playing games so she can watch," he is "playing games while ignoring her." So it's no wonder that Milly was able to trivially win her over.
I'm pretty much here for the Depravity path, however. I will spare you the lurid descriptions and simply keep it to "I quite liked it, I am looking forward to more of this, especially when Milly's lust turns on her family, and even further down the line when the pregnancy options are added." However, I do have to confess that futa on futa is not my jam, but it's avoidable, so I am glad it is there for the people who do like it.