As some have said a Yak 1 (VK105P (or PA)) would add mid 41 to mid/late 42.
I would hope that when the 9T and 9U are remodeled the T gets and M option for scenario use.
+1
It is good to see that HTC is working on Yak line adding new Yak-3 and Yak-7b
1) I would recommend to add early war Yak-1 (m-105p) which will cover 1941 scenarios like "Barbarossa" or "Battle for Moscow"
2) It would be very good to convert existing Yak-9T into hybrid Yak-9 (m-105pf) model with the options:
a) 20mm cannon (Yak9/Yak-9M - the most standard version)
b) 37mm cannon (existing Yak-9T)
c) 20mm cannon with additional internal fuel tanks (Yak-9D/Yak9DD)
These additions will pretty much cover the whole Yak line (with the only one exception of Yak-1b which can be well substituted in scenarios with Yak-9 20mm)