If you feel closed is best for you then go for it! BUT I would say do your research first
Semi-Open adoption is still widely accepted and from the few agencies I talked to about domestic adoption was still a widely asked for thing by both Bparents & Aparents.
Personally, I'm not thrilled with the idea of having the Bfamily become "family" I'm happy to exchange letters, pictures and medical info...but I don't think I could deal with monthly visits, going on vacation with my bfamily or allowing my child to go and spend the weekend with them...EVER...which, for me, was one of the factors in choosing international adoption(not overnight visitation, but level of openness).
BUT that's me...I've just seen one too many open situations go bad with my friends and family...that is NOT to say that many of our wonderful members here don 't have GREAT relationships with their Bfamilies or Afamilies...but it's about what works for you and your family.
We all know our limitations, and there is NO shame is being honest with yourself about what you think you can deal with. I agree whole heartedly with what Mommy24 said, DON'T make promises to PBparents about the openness of the relationship if you aren't planning on keeping them. You may have to wait a few extra months to find the right situation, but ALL types of adoption are still out there, you just have to be patient and find the right agency
Best Wishes