It is human nature to think about what we don’t have… it’s the “grass is greener” thing.
It sounds as if neither are actually a good fit for you. What you need is one man with all the great qualities you love!

I would not try to force anything but step back and see how things work out.

Perhaps you and the great guy guy/ mediocre sex could work on that aspect of the relationship.

Is it a lack of chemistry? Because you cannot create chemistry but you can create new ways to enjoy intimacy.