Xcom, things became better. I tweaked my view distance to medium, preload radius doesnt seem to make any difference to me, but I still have about 22 frames(for each eye), while looking the units direction. Else I have stable 45.
Could you disable the clouds at all, so I'll check if that make any improvements.
Edit. Its bad, that we cant take slots from the fields in the middle of the map, such as Chippelle, Cricqueville-en-Bessin & Deux Jumeaux & Cardonville, Lignerolles, etc.