Here’s my story of how I spent numerous days trying to get myself some good-fitting boots, but still achieved no result.
I have short, slightly wide feet with high arches and high insteps.
Here’s a screenshot from the Fischer app

Real measurements:
254mm/99mm left
250mm/99mm right
I’ve tried around 20 boots and almost all of them were crushing my insteps immediately even after sizing up. Here are the ones that I’ve made notes of:
FISCHER Ranger 110 275 - toes are fine, instep crushed
HEAD Kore 2 270 - pinky pressured, instep crushed
Salomon Shift Pro 265 - pinky pressured, instep crushed
Atomic Hawx Prime XTD 275 - toes are fine, instep crushed hard
Rossignol Alltrack Pro 265 - toes are crushed, instep pressured
Tecnica Mach1 MV 275 - toes are slightly pressured, instep pressured moderately
Couldn’t find any popular high volume boots like Magna in my size to try.
So out of in-stock options Dalbello Panterra 120 260/265 are the only boots that didn’t immediately crush my toes and insteps. I spent 30 minutes in the store and my feet felt fine. The size also felt right length-wise. There was some light pressure on the instep, but I thought it would go away over time.
So I got the Panterras.
Every time I skied my instep hurt, fingers from the pinky side went numb, some pain over the ball. It was worse when I was not skiing but just standing in the boots.
I went to a boot fitter, got myself a custom Sidas sole and heat-molded the boots.
Heat molding helped with my toes, but didn’t help with the instep (maybe it was compensated by the custom sole).
The boot fitter said it would’ve been easier to make the instep bigger in 2-piece boots, but with a 3-piece there’s now only an option of grinding the plastic sole to lower the feet.
So I agreed and grinding actually did help with the instep.
Now this is what happens:
When I buckle to the middle - they feel loose, especially above the front of the feet near the big toe. Tongues feel loose. There is enough control for simple skiing, but trying to jump/butter feels uncontrollable.
When I buckle hard - everything starts hurting again, the pinky toes, the insteps.
I’m going to the boot fitter again to see if there’s anything to do.
But I guess I screwed up since now my boots are too loose in the front?
P.S. Could you guys please recommend some more boot models with shells that would be fitting to my type of feet (high insteps, wide but not too wide)? I'd like to try some more options