Actually, my foot arch is medium/high in both my feet and it still recommended me being in a vapor skates. So not sure about that foot arch thing you talking a bout.
I think that your volume fit looks good to me. If your heel feel locked-in plus that you don't have any lace bite, you should be good to go. You won't have to crank your laces as hard as you're used to because the vapor is more close to the top of your foot. You would probably fit in a supreme skate too, but you would have to crank the laces a bit more to have more wrap and also note that a supreme skate would have more width in your heel area meaning that you could possibly lack of heel lock. Lots of factor to consider in. Personnally, I would go in a less roomy skate than the opposite. Heel slippage cause far more trouble. Are you the kind of guy who crank the laces as much as you can on top eyelets? If so, as soon as the tongue breaks in, you ''might'' feel lacebite...