There were so many ideas posted that I really don't need to put in my two cents worth. I love to quilt, but honestly, the quilting world is also a market for people and manufacturers to make money. The big machines though nice are there for the main purpose of making money. If I step on toes, sorry.
It's not the machine that makes the quilt but the quilter. If your wife truly enjoys quilting, she will gladly quilt on any nice machine you give her. There are plenty of low end machines or used expensive ones for a price that is reasonable and has enough bells and whistles to delight any new quilter.
I wouldn't buy a concert grand piano for a beginning piano student any more than is it a good idea to spend thousands of dollars on a high end sewing machine for a new quilter/sewer. If money is a factor, you will never get even half back of what you invest in the machine.