I don't think getting back together
solves the core issues you had with him when you were together. You
either didn't understand his other obligations, or he really was
neglecting you. Why do you think things would change if you got back
together? And what are your (and his) plans for when you graduate from high school? Sixteen is a little early to be thinking "forever" with anyone!
If I don't hear from you, my best advice would be to take the urgency
out of this and let things progress naturally. Forcing something to
happen could backfire on you. How you socialize with each other, now,
gives him the opportunity to be in control. And that's what he wants,
presently. I'd let him know that was okay, and start showing him you
have a life with a rosy future even if you don't make it work. You
never, ever want to appear needy, or desperate (as you know). It's
demeaning, and off-putting. That's a burden to him, and something that
would keep him from giving the relationship another try. But be aware
that your past problems with him won't go away just by wishing it so.
These are real problems that would need to be corrected in order for
your relationship to work, even if you had a chance with him. You have
to figure out if your feelings of being neglected were based on insecurity, or
they were legitimate. A good relationship allows some independence and
freedom -- and the trust that goes with it.