I agree with those who prefer the vintage straight stitchers. They usually have a narrower body above the needle area which gives a better of sewing area than the more boxy new machines. I tried free motion on my Singer 9960 and oof...it was a struggle. Then I tried a vintage straight stitch Monarch (classic black Singer 15 clone) with feed dog drop and it was a lot easier. I finally understood why people actually enjoyed free motion quilting!
One note, some of the foot controllers on the vintage machines are kind of zero to sixty in speed. If this is the case on the machine you get, it's pretty easy to change it to a new electronic foot controller. That really helped me with variable speed control and my stitching improved. There are videos and tutorials on how to change a foot controller on the internet. Good luck and let us know what you get.
MJ