In short bought new boots, added a pads to increase heel hold, think it worked.
(Also don't modify your boots unless you're a bootfitter)
Long Form:
Ended up sizing down to a 25.5 Fulltilt First Chair 8 from a 26.5 Rossignal Alltrack Pro 110 with a Intuition Power Wrap Pro. Loved the Rossi's but they felt very stiff, so I was looking for something softer and that fit my foot better. Over the course of experimenting with some shims in my Rossignals along with some foot beds and instep pads to help get a snugger fit over my low instep I finally checked the over all shell fit and found out I had 2 fingers plus of room in my shell, which was a shame. The boots still fit decently enough that touring in them is still fun and enjoyable with minimum boot slop, but I wanted to have an inbounds boot that was a much better fit.
So I sized down to the Fulltilt First Chair 8 in a 25.5 after quite a bit of research into the fit of the boots and the cost. I figured I was making somewhat a shot in the dark but I thought I would get pretty close to what I wanted. Plus I had an extra size 26 Intuition Power Wrap Pro Liner in case I thought the stock Fulltilt liner was to soft or packed out to easily (Which is the reason I have the Intuition in the Rossi's as the stock Rossi liner had less than desirable heel hold). Unfortunately I only got one day of terrible conditions to test them in at my home mountain before the whole COVID-19 hit. So after touring in the Rossi's for a while I got some day makers added to my touring quiver so I could test the Fulltilts.
The initial thoughts when I was skiing inbound on icy groomers and messing around on rollers in the park was that the boot was substantially softer than my Rossi's which was a bit of a learning curve but nothing bad, just different. The Fulltilt had good power transmission through a turn and felt really good for making precise movements with the skis when trying daffy butters and tip and tail butters over the rollers. The only thing that left me wishing was the lack of heel hold during aggressive tip butters. The liner felt like it was lifting out of the heel pocket in the shell of the boot. Initially I thought it was the liner but after swapping the liner with my 26 Intuition Power Wrap Pro Liner (Which felt like it stiffened up the boot a good deal) I had the same problem.
So I ended up trying to increase the heel hold with some scotch removable double sided adhesive squares meant for hanging things on the wall. That way I figured if it didn't work I could easily remove them with no ill affects. So far my initial floor tests have gone well with the liner no longer lifting up in the shell. Hoping to test the boots more later this week in addition to next season to see how it works and holds up.
Pictures:
