Sounds reasonable & house rules
This cost is in line with the "quilt by check" costs in our area. Your wife very well might like to piece and pay someone to finish her quilts.
My husband restores cars. The rule at our house is "don't ask, don't tell, you know what you can afford." Just as I wouldn't tell him to paint his car with rattle cans, he would never tell me to quilt it at home. I know the longarm quilter can do a better job on a huge quilt than I can, and that's up to my judgement.