I have used 'big stitch' quilting for 15 years since having it taught in my shop in Dallas TX. The stitches are not huge! If you get 5 stitches to the inch you should have no problem. Usual 'fine' quilting takes 9-12 stitches to the inch, all counted on the top layer.
Here is a close up of one I have done using wool batting and 30 wt. Sulky cotton thread with a #7 between needle from Richard Hemming. (That's a quarter beside it.)
Jan in VA