Here are some things I would like to see / need to be added to Russia tech-tree next update.
Mig-9 NS-57 (57mm)
IL-2 NS-45 (45mm)
BMD-4M with x8 Kornet ATGMs
Kurgunets 25 (30mm and Kornet)
Centuro b2 120mm (tested by Russia)
2S35 Koalitsija-SV twin 152mm howitzer
BM-21 Grad
Ka-52SK (South Korea armed with 20mm and x16 NT-D / Spike ATGMs)
Not all would be added, but even a few would be very nice.