Risport RF3 Pros heel pocket too wide, broken down easily

Hey everyone. I’m (23M, 174cm, 100kg) skating 4 hours a week, currently working on my axel and double salchow.

I bought Risport RF3s with MK Pros in April 2026, but 4 months in, I’m constantly getting off the ice to retie them, and doing any sort of knee bend loosens the boot entirely. Pro shops in my country are unreliable for comprehensive fittings, and custom boots are completely out of my budget.

Here is exactly what I'm struggling with:

• Heel Slip & Gaps: The heel pocket is too wide. I've been using achilles gel sleeves purely as stuffing to fill the gaps between my foot and the boot. If I crank the laces to lock my heel, my forefoot goes completely numb. This isn't a length issue though, as I can also feel the tip of the boots with my toes.
• Arch Pain: I use Superfeet Carbon Yellows, which helps alleviate my arch pain, but they don't fix the overarching fit issues.
• Foot Shifting: Due to inward pronation, my foot physically shifts around inside the boot—especially on my left landing foot during jumps. This makes me completely lose my outside edge. Overall, I feel like I'm standing on top of platforms rather than the skates acting as an extension of my foot.
• Boot Breakdown: I’m simply too heavy for this stiffness rating. The tongue offers zero support, and the forefoot loosens terribly on deep knee bends no matter how I tie them.

My Boot History:

• Jackson Marquis (2014): Fit perfectly with zero pain, but obviously too soft now. I know Jackson redesigned their lasts recently, so I'm not sure if modern high-level Jacksons will still fit me the same way.
• Edea Chorus (2016-2026): Painful arch pinching, and I hated the loose-ankle feel.

What I'm Looking For: I need a boot stiff enough to support a 100kg skater doing doubles, with a traditional, secure ankle feel (not Edea). It needs to lock a narrow heel without crushing a wider forefoot.

Has anyone with any experience navigated this? Would love to hear your model recommendations before I decide on anything