@andrestu - thanks for the comments - very useful. I agree completely with the Red Army comments. I added the "Spring Offensive" event that grants them many free units every March from 1942-1945 (game turns 38, 50, 62, and 74). It's possible for them to receive between 20 and 29 free units every year during this event.
I was still tweaking those numbers when I released the mod, so it looks like it could use some more refining. Originally, the USSR had a larger army at game start, but the problem was it consistently overran Finland in a way that just seemed too a historical. So, I reduced the Red Army at game start to give the Fins a chance, then added the free units later, spawning further away from the Finnish border.
I was OK with using a smaller army at start of game to reflect the officer purges of 1938, which left the Red Army almost completely combat ineffective - something that Barbarossa demonstrated quite well. Obviously, during the course of the war, the performance of the leadership improved, and was on par with most Allied armies by war's end. But even with a rather large army in 1939, tiny Finland acquitted itself quite well.
This growing effectiveness dynamic is demonstrated in two ways: (1) Nerfing the number of Soviet units helps reflect "combat effectiveness" of the Red Army at the beginning of the war, and (2) the Spring Offensive free units event is meant to demonstrate overall improvements to the war effort over time.
Personally, I think the first goal (1) works, but I'm starting to think the second goal (2) does not. By 1943, the Red Army should be steam rolling, at least through the Balkans. Which leads me to believe the Spring Offensive numbers should be larger, or perhaps a Winter Offensive event should be added as well. Maybe?
Getting the AI to build terrain improvements is almost impossible. The hard-coded logic looks at certain "flavors" for the improvement, then decides what to build based on it's assessment of what the economy needs. Since much of the game's normal economic development logic is meaningless in a 7 year scenario, those choices will almost never reflect what a human player trying to defend his border would do. You can make "suggestions" to the AI, but they almost always ignore any tweaks in the code of the mod. Basically, if the TI's aren't on the map at game start, they won't appear where they should, ever. Terrain Improvements also represent a bit of a human player advantage, as they can actually use these improvements in strategic locations. It's one of the reasons I've nerfed some of the benefits of these improvements - so it doesn't get too OP during play. Most of them are there for looks, to give the game a more WW2 "feel..."
You're not the first person telling me the SS units don't seem to spawn for the human German player. I'm a little surprised by this, as I've seen them work just fine during testing. But the code changed soooooo much the last couple of weeks before release, I think I may have made a few changes that stopped them from spawning for the human player. I've just looked at the code and believe I have found the offending lines. I'll add this to the list of fixes for the next version. This bone-headed error also makes me want to move this scenario's fix to the top of my schedule, meaning I'll start working on this next, instead of later in the month.
Appreciate the helpful comments and suggestions! Tack så mycket!