Howdy! I made my first quilts on a utility sewing machine without all the fancy do-dads. I even free motion quilted several king quilts with that old machine. It can be done( and well enough to win a quilt show ribbon, I might add ).
It's been 9 years since I started and last year I finally did upgrade to a 6600.
If you're interested in FMQ then a small machine isn't all bad. All the experts will tell you it's easier to just practice on small sandwiches until you feel comfortable. You don't need more harp space for that. Good luck!
Ultimately, the decision is yours. One thing is for certain--the longer you wait and the more money you save, the more options you'll have.