Any changes are allowed by mutual agreement, provided that HL+U will be played.
I will mention this in the first post.

Added 3 minutes ago

What is the fundamental difference between 8xm8b and a? I don't like the concept of this template (or 8mm6), so I decided not to include it this year. We played with them for 5 years. Why not try something different this time?

If you ask such a question, I get the impression that you haven't even played this template in its second version. The difference is in the adjacency. Previously, to avoid early encounters, we played the original 8xm8a with red against pink.
Then, both players were in diametrically opposite locations. In version b, the location of blue was corrected and moved to the place of pink, and pink was moved to the place of blue.
As for whether you like it or not, it's great that you specifically don't like this template. But maybe it would be better to conduct a poll regarding the pool of templates?
Because I didn't understand what was wrong with the Russel Mix.