First of all, it's hard to critique cause it's only 2 minutes long, so I'll say My subjective opinion of what dev should do.
Focus on story from perspective of one character, to avoid it turning into a mess, since it's Your first project.
Define what is main fetishes of a game, choose 3 as main focus, while others will appear next to them. Choose those You like.
Talk with people, don't hesitate to ask for advice, there is dev forum here on site.
Now what I would like to see in game (it's just thoughts, not demanding to add anything):
Piercing and tattoos, lactation, regular pregnancy, let the queen to have fast gestation with help of magic potions or being blessed with it during game (or cursed, depending on point of view), costume changing to more and more revealing and sexual with progress of a game, queen starting to enjoy sex more and more as she gets more corrupted, queen wearing enchanted dildos and buttplugs as amulets.