For the canvas and flip etc stuff
Maybe for some tech variant units having brightness applied would probably the simplest. Basically the stuff covered in the pos props. Then for the canvas stuff to work with the flips, basically I was just trying to get something that would play alright with this part...
#units.transform.brightness.<player> (optional) allows the brightness (-100 to 100) to be adjusted when units.transform.color is set
#units.transform.brightness.Russians=25
#units.transform.flip.<player> flips the player's units horizontally
#units.transform.flip.Russians=true
#units.transform.ignore provides a comma delimited list of units that aren't impacted by the above units.transform properties
#takes the unit's name and applies to all images shown for that unit including damaged or tech improved images
#units.transform.ignore=factory,fighter
For the blend options available I think alpha f2 was alright for something subtly lower contrast
map.mapBlendAlpha=0.2f


That's a pretty easy one to add, like just from editing a line in the map props, but sorta the rationale behind choosing those pretty high saturation defaults for the hexes and such. I can't remember what the default is no blends, but it's basically similar to alpha f5 I think maybe?
For tripleA to do all units as a square, say 54x54 px applied to everything pretty sure there is a way to do in the props or game, but I can't remember what exactly it's called. I've done it by accident before where everything will go to the 48px default size, or I think if the graphic is way oversized it may then morph it to fit the standard square, but couldn't figure out just now when messing around lol.
Pretty sure there's a way though if one wanted to do a standard warp for all the units at once, though it's not a view setting on the fly.
Anyway I think should be enough room for the flags on/off option to show alright if I just add a sliver of canvas for some of the narrower units, like if clips too hard into the unit, but for the most part seems to work ok.
ps. Just to further clarify. If we include the Alpha channel blend this can be used to make the map more/less pastel incrementally. Example alpha 0.02f shown above that can be set 1-10 so 0.0f or 0.1f look very close to the default (highest saturation.)
0.2f or say 1.5 f or 2.5f those will pass through white making it more pastel. 3-5f is brighter etc. In the PoS2 props the first mentioned is linear light, but linear light is effectively a monitor setting now, I mean it's just reducing the brightness bascially. Alpha channel blend is more modular and more useful. I think the only other candidate worth the mention is overlay.
Overlay will essentially double the opacity while preserving the brightness. Multiply will do the same but reduce the brightness, they're largely similar. These are not really set to be modular in the way the alpha channel is though, so you can't really increase or reduce the "pastel" effect with the different integers there. The image produced is also quite different, because it's taking the relief layer and essentially layering that again on top of itself a second time. Here is the resulting image for that...

It's kinda cool, but I don't know if most would prefer that. To choose a blend, this would be an entry in the map properties txt. Like just added to the bottom. I would add the Alpha in as the default. This means user can click blends and it will show a slightly lighter version of the default. And if users wants it more low contrast they can increase the Alpha channel to crank that, basically like adding white in heavier amounts to the colors as they paint.
oh here's that one dude for Japan just so I don't forget added him to the big folder
