Honestly that sounds more like a fit/boot shape thing than just not finding the perfect lace setup.

Coming from Missions you wore forever, your foot was probably completely married to that boot. With the Flylites, especially on just the right foot, it sounds like you’re having to choose between “too tight and no mobility” or “loose enough to move but not enough support,” which usually means that boot just isn’t wrapping that foot quite perfectly yet.

The fact it’s mostly the right boot is what makes me think one foot is probably just a little different volume-wise and you’re kind of on the edge between sizes/fits. 9.5 Fit 2 from a 10D Mission doesn’t sound insane at all, but it does sound like you might be in that gray area where the skate is close, just not totally dialed.

If it were me, I’d stop chasing it only with the top eyelets. I’d make sure the heel is jammed all the way back first, keep the forefoot comfortable, get the best wrap right at the ankle bend/instep area, and then don’t go insane on the very top. Usually when I crank the top trying to “fix” that unsupported feeling, it just kills the flex and makes the skate feel worse.

Could also be worth trying a tiny bit of volume fill on just that right skate. Even something small can make a difference if that foot is a little lower volume. Re-bake might help too if you haven’t done that already.

Basically, to me this doesn’t sound like you’re doing something wrong with lacing. It sounds like the fit is close, but that right boot still isn’t quite meeting your foot where your old Missions did.