Happy New Year Chas. I think it's great that you are asking for thumbs up and down on OtO. Not many thumbs down as this was a classic.
Regarding hex size, normally bigger is better, thus a positive. But in this case as I mentioned above because of the low counter density and longer LOS, you could "justify" going to slightly smaller hexes. I would only do it if you can increase the board width a few hexes. Wider playing area will allow the defense to spread out a bit more (and the attacking Ruskies as well) and this is important considering all that OBA which is flying around.
CG idea, get rid of depletion. You SSR it out on the first AM scenario making all RGs full. Well over half (maybe even 2/3's) the forces for both sides are either At-Start given or purchased the first AM so most RGs are not depleted anyways. I would say just continue the trend. Especially considering some of those big purchases that have a 2/1 depletion number. HUGE difference if a side rolls bad. Just slightly increase the purchase points to account for the larger amount in the budget.
Another CG idea. Tighten the leader variance roll per company. Instead of a "snakes" being a 10-3/9-1/8-0 and "boxcars" giving two Sgt Shultz's (8-0's) make the leader rolls fairly even. Tweak it so standard issuance of a 9-1/8-1/8-0 is given for each Coy. (Russians get slightly worse) Counter this by upping the Leader Battle Hardening table used in refit. Maybe allow two rolls per side or to the winning side (perhaps the winning side gets a second roll but w/o the -2 mod) If the leaders survive the battles, now they have a better chance to get that -2 modifier.
Think out side the box on these CG rules. Just because RB did it or didn't do it a certain way, doesn't mean you have to as well.