I think should better half the defences from the upgrades and rings, that's clearly too strong. I only died from vore or traps, dmg is nothing in the game xD
Did you think about it to give the Lust-Value a little bit more purpose? Maybe add a ring, that give you dmg proportional to Lust? Or add 2-3 NPC's with that you can interact with a special event with enough lust.
And if you add a ring that does dmg after ero end, then it adds a little more play-styles I think.
The most bosses have to less hp, they dies to fast. The witch, hi-tech and swamp bosses are ok with the hp.
I enjoyed your game, thanks for your work! :3