@Chef23 I also have cold feet. I have noticed that the warmest boot is not the boot with warm liner etc.. For me the warmest boot is the boot with toebox which allows to move fingers (at least to have a little freedom to move). For years I have changed more than a dozen (if not two) boots and liners. And paradoxically, the warmest were very narrow sport boots with thin liners. Current boot is 95mm wide whereas my foot is 101mm wide. Paradox.
In the lift up I unbuckle 2nd from below and move toe fingers. It helps.
When temp goes colder, below minus 10-15C I use heated socks (Lenz, with bluetooth feature - very comfy) in order to use same insoles.
Also people say that neo BootGlove is a good thing (though looks strange)
Warm (thicker) liner requires more tightening and makes things even worse by constantly squeezing foot.
Intuition is irritatingly hot in spring time.
IMO - the most important is to find shell that fits anatomy of your foot, than experiment with liners.
All manufacturers have their own so called "basic foot pattern". It is turned out that my foot is Atomic pattern, and 10 years in a row before I have tortured myself adjusting different Fischers.
When you find your shell it makes a miracle.
Hope it gives you another 2 cents of information.
As you correctly noticed - it is more about circulation and it very much depends on map of your foot vessels.