@KingQ0916 Hey!
I just finished going through all three stories and I really have to say that all three of them are really incredible and has plots, that I haven't seen before. They are very intriguing, exciting and full of tension, all kinds of.
Though the 2nd and 3rd story has similar genre of Fantasy and Supernatural than the 1st one.
Though all three of them have excellent premise and potential. It's really hard to choose from. I would say start with either 2nd or 3rd one (I would say 3rd) or you can write them both at the same time, it's up to you.
I would suggest that you keep the 1st idea on hold for some time. It follows the similar age-gap, forbidden, Romantic, thriller and Adult-themed path. While a kind of unique plot the themes are common.
Now, it's up to you, what you wanna go with. I am happy with whatever you choose. 。◕‿◕。