In my opinion, Illusion has stopped developing games as such and produces creation software with some "gameplay" tacked on. Koikatsu is a prime example of this. Gameplay is not worth many words written down
Ultimately it's subjective. As they say "Things you enjoy doing is never a waste of time.." Considering most 90% of all protagonists in FPS's are silent.
In RTS's and unit combat they always refer to you as commander/captain.
Stands to reason people like the immersion.
I will try and not gonna get long winded but truth is most people like to fuck... And in this "modern" era. There are very few wonderfully "choiced" life-partners. So we are build them ourselves. Even cave paintings showed this. Hunting food, Identity, Sex and making Children.
(Chauvet Cave in France. These paintings date to earlier than 30,000 BC (Upper Paleolithic))
boil it down "game play" is "lusting/fucking/loving the one you want. how and when you want it".
I'll be honest the only reason I registered here on f95 for the Illusion HoneySelect/AI-Girl/Koikatsu games.
Before HoneySelect 1, I was okay with the Thrixx SexVilla3D with most importantly the community that did the right thing and stopped those micro-transactions. And built custom Animations.
I did play through PlayHome. I found that story to be really warped/twisted and not to my liking.
I have played Koikatu (I haven't tried AA2. Is it more engaging? Is it better or worse?).
I really wish Studio Neo 2 would be it's own thread and that people would make a concerted effort importing what they have made into Ai-Girl and HS2.
Personally too many people are pushing for more features for Studio Neo 2 from the core modders rather then expanding what AI-Girl and HS2 can do.
Ultimately, if we want to be completely honest. Illusion makes software that is designed for a particular thing... Sex Ed. What we want or get from Illusion is completely secondary.