You have an exceptional game here. I loved the original demo and I have been watching your game to see how it progresses. I believe you should make it what you want it to be. Ultimately, its about two kinds of fun: kinky and entertaining.
Linear is great, open roam is great. Keep the story interesting and the controls simple. Add in rewards and consequences.
Personally, I liked the multiple consequences you could have before losing the game and the scenes you get respectively. I liked the challenge of the puzzles: mostly simple enough without outside help, but challenging enough to keep trying after failing...just to see what you get if you win.
Keep working it, don't overwork yourself, and don't think that you have to keep something because it's popular: it's your game.