I would FMQ it. You don't say how old this quilt is or did I miss that somewhere? The fabrics don't look especially old. Quilts have been machine quilted since the late 1800s,I'll admit most were hand quilted.
Just because Grandma made it doesn't equate antique. There are lots of Grandma's on here who give grandchildren quilts.
I do like the quilt very much, finish as you desire. Your free motion is very nice.