I'm learning to free motion quilt on my vintage Bernina using muslin practice "sandwiches". Is the bed of your machine flush with the table? I had to pull my original sewing table with fold up extension table out of storage and wax the surface so it was slick. Reducing the drag on the quilt is essential. I'm getting much better at managing the stitch length and controlling the stitches since I did that. I've moved on to making patterns on my practice muslins.
I also discovered that I can see and move the fabric more easily when I turn the machine so that I face the sewing machine head. In this position, the quilt roll is behind my work area instead of to the side, and I pull the quilt forward towards my lap as I quilt.
Of course, this doesn't work with the configuration of the sewing table I have. So I have ordered a vintage Singer 15-91 and will build a custom table top so I can turn the machine sideways for quilting larger items.
Harriet Hargrave's book, "Heirloom Machine Quilting," has really helped me.
P.S. I have never had to change the upper tension on my Bernina, which always has perfectly balanced stitches. It was really hard for me to change the setting for free motion work! I used different colored threads so I could adjust the top tension until it was balanced. I did not have to touch the bobbin tension. The tension issue is another reason I have bought another machine, so I can keep it set up solely for free motion quilting, and keep my Bernina set up for piecing or garment sewing.