I hand quilted for 10 yrs with my quilts tight in the hoop!! Boy was I happy when I discovered that I could make it loose. Woww what a difference!! (Talk about dumb!)
As far as my finger underneath I try to feel the needle just as it barely comes through the fabric, not far enough to prick me. This gets me smaller stitches underneath. They were always bigger than the front before I started doing it this way. Bonus: My finger doesn't hurt!!!!
After I found a thimble that fit I just kept it with me everywhere I quilted till my finger started to hurt & then I'd put it on. After a while it became a habit. The key is finding one that fits. I found mine at a thrift store. What will I do when I loose it? I've already lost one!
I use wool batting for hand quilting (most of my machine quilting also!) It needles wonderfully, & helps me to get smaller stitches! Warm in the winter & cooler in the summer! I try to catch it on sale.
As you can see it is a journey. Find out what works best for you.
I hope we all keep learning from each other!