The OP mentioned that the other person is putting efforts to talk more and share, but their pace of opening up isn't what OP would like.
An introvert isn't going to start pouring out his/her heart to anyone within a month. These things take time, and the good part is that the person is trying. And OP needs to make efforts too if they want this connection to work out. In their post they have focused on the differences, their perspective and what they want, not on the other person and what is, or could be, between them.
I just don't want the OP to screw up a good connection only because that other person is an introvert, doesn't have much of a social life or friends, and has some flaws that most of us do (overthinking). That's literally basically who an introvert would be, and they shouldn't be put under scrutiny for being that way. Give it some time and see where it leads, that's only what I want them to do.