Originally Posted by
blazin
Not of much use to the OP now, but re: lack of good cassettes for AXS setups: I use the e*thirteen 9-46 12 speed cassette with my AXS mullet build (and 40t chainring). Plenty of range, I spin out on descents but otherwise am able to hit 25+ mph in flats while climbing steep walls, with somewhat noticeable gear gaps.
I figured there were more cassettes out there to choose from but stopped looking when I made my decision to go Di2. I tried the 9-46 11 speed cassette on it when I was trying to find something cassette wise that worked better. I liked the range and as you say the climbing was good, however I spun out quite often.
I realized what I wanted was smaller gaps on my cassette rather than wider range overall. So 2x I went.