I do plan on making a romance route for every character and have a lot of their events written down in documents already, most of their stories are already thought out, however, romancing them is completely optional and not NECESSARY to progress in the game.
I find your suggestions very interesting though, thank you very much for that! I'm definitely going to see that I try to implement some of your ideas, if possible, even all of them.
Building affection with your desire is possible even without romancing them, but the mansion will mostly be needed for that since that will be the point at which you can start giving gifts and doing "other actions". Depending on their personality, they do actually like certain actions more than others. I was already thinking about doing something in the way of unlocking new features as they grow to like you more, it's definitely going to happen, no matter if you are romancing them or not, so you can look forward to that!
As for the "animation" part, I could try, but I'm not the best when it comes to animating, so I can't promise anything in that direction.
The idea of dominating the aggressive ones does sound tempting, I'll see that I'll do something with that!
With the "touching characters in different places" part, you've actually perfectly described the dreamscape which is already implemented for 2 characters! However, it is another feature that becomes available as soon as you have the mansion.
And I don't mind the long message at all! In fact, it really motivates me to work on the game when I see that people care so much about it and like it! Thank you for supporting my project!