Welcome to the board. I would finish this quilt with the walking foot straight lines.
Then make small sandwiches 20 inches roughly. Now this could be fabric you like
And will join them into a quilt or keep as sample as.just practise. Remember all those handwriting
Lessons at school , or learning to drive and co- ordinations the foot hand ye etc. we have all
Spent ages practising. Some people just using paper and with a very upright pencil practise the movement
Of the material under the needle. You may find it is not the machine but that you are just changing tensionunnecessaryil. Keep going it is fun but not on your precious quilt.
Ps we have all had to undo