A couple more variants would be awesome for sure. Don't underestimate the 23mm AP.
37mm cannon is available on single seat IL-2 only one aircraft was fitted with these 37mm's it was in combat service tests November/December 1941.
Then is squadron strength in December 1942 & combat in Jan of 1943.
Not sure though what the time frame is in early war AHII?
Most likely a mid war option with the 37mm.