Wouldn't my first tile (which is indeed not wide enough, I noticed this soon after having posted it), be similar to the flat brown one some posts above. It's 8 wide and 2 high, and yours is 40w 10h. My big brown top down hexagon is 7 high, but I'm not sure if that's exact.
asin(2/7) in degrees
90 - 16.6015496 = 73.3984504
Yeah, that's a 73, but not an exact match to yours.
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After this test below I concluded that doing... smoothing, or anti aliasing at tile level (half forest, etc) will probably just make the strategy element suffer because the map is less distinct. I can probably vary the forests a bit, but not in density. I'm thinking that it's better with some more Boolean terrain cases.
Also, I should add some faint lines around the edges of the hexagon where the ground shows.

Painted sloppily at 5x, scaled down, sharpened, masked.