Rub it down with a little tokonole or Tragacanth Gum. Wrap a piece of canvas around your boning tool and rub away. Alternately, I have several brass punches that I use with or without the canvas. It always gives me good results. Good luck.
I have never used heat. I always case it and smack the stamp with a mallet. My stamp has a screw -in handle to make it easier. I do have a larger stamp that is used with my Harbor Freight Arbor Press.
I found some very small bevelers and they help out when beveling tight cuts. I think I found mine on Etsy. I know Barry King sells some steep and small bevelers as well, just didn't want to spend the extra for BK. The one's I got work well for tight spots.
Great job on grouping the leaves in the corner, then coming out from there with them. Nice design. Something to consider on the next one...may want to have the circled parts below so they don't show the flesh side of the leather. Maybe cut an additional piece the same size as the flap and sandwich the ring in between. You also may want to touch up that thread end with a lighter. Love the colors too.
what didn't you like about it? When was the last time you used one? They have made upgrades. Not saying I would buy one either, they are pricey...I just have the luxury of borrowing one.
I have the luxury of "borrowing" a Glowforge. It can do awesome engraving, but has issues cutting 4-5 oz or thicker leather. There are better solutions for cutting, just don't know what the best is for both.