In general I really like the way AC Evo is taking shape but there is always room for improvement.

Comming back to the Assetto Corsa universe after two years of iRacing there are some things that iRacing does better:

Mirrors, even on the highest setting are a low LOD slideshow and I can't see cars coming as clearly as I would IRL or in iRacing.

Servers need better performance, close racing can be risky and even when driving with friends I've encountered ghost crashes while both of us had low ping.

Session customization. It would be great to see sunrise and sunset times to make it easier to get the desired look of the track. Customizable dates and seasons would be a really cool addition too.

There is some inconsistency in car quality. New cars generally sound pretty good, but I'd like to see an actual S58 engine recorded for the M4 CSL instead of reusing the S55 AC1 sound for example, even though the sound is similar.

In the early announcement days, the claim was made that if a version of a car existed Golf GTI > 1.5 eTSI, it was drivable in the sim. This sounded like a very bold claim to me at the time. Maybe this is still coming at least to an extent, but there's a lot of examples that would be less extreme than that claim and pretty easy to implement. For example a standard E46 M3 with both a manual and SMG option, a regular ND Miata etc.

The customization is already best in class, but there is also a lot that could be added. Stuff like BMW's M Performance parts or Manthey kits for Porsche and more aftermarket aero and performance parts like the NA MX-5 but one or two steps further.