Just a thought for larger quilts - longarm quilters will sandwich and baste a quilt for you and it isn't as expensive as them quilting the whole thing. Maybe $40 for a queen size quilt? I don't know if hand thread basting is weaker but do know that machine thread basting will definitely hold up to machine quilting. Definitely consider basting with the washable school glue as it is easier and much lighter then pin basting.
Glad to hear of your frame that will save your back. I too have back problems and have to think ahead all the time to help keep injury away.