Is this an unreasonable custody request?

I was never married to my son's mother, but I immediately established paternity and we raised him as our son. Unfortunately, his mom and I broke up and circumstances forced me to move back to my home state of NY; they live in SC. I keep in contact with my son as much as I can. The only problem is that we never went through court because at the time we came to amicable agreements regarding visitation. Now that she is engaged and has two more children with her fianc�, those agreements aren't so amicable anymore. I realize that I will get what a judge gives me, but here is what I am hoping for. I have no problem with her having sole physical custody, but I would like us to have joint legal custody and I would like a court enforced interstate visitation schedule. We try to visit as much as we can and we had had a trip planned for May. My ex has told us that she does not want us to come down now. By us, I mean me, my wife, my mother, and my son's half brother. I want to be a major part of my son's life and I fear that while it was admirable of us to try to work it out ourselves, I need to have my rights as a father protected. So is what I am asking unreasonable?