Heads from Skyrim.

It's interesting to see how quickly retopology is done there, judging by the appearance.
And for a quick, one-click option, it looks very, very good.
I always wanted to ask if the faces from Skyrim are too heavy for Heroes, but now I see that you're simplifying them, and that's the right approach.
And doesn't smooth add polygons? I mean, is it just smoothing groups, or is it a multiplication of polygons? Because if it's a multiplication, then it's a pointless situation: you multiply first, then divide. If you reduce it directly without multiplication, then it should result in a cleaner version.
Regarding the squares on the first face. It's just that the smoothing groups aren't configured. I can fix it in Max with one click. This is in my guide on transferring a model from the 7th game. Or maybe smooth does the same thing here.

Added 2 minutes ago
The shadows on the reduced model do look a bit rough. I know how to fix this in Max; you need to use the edit normal modifier, select all the normals, then break them apart and join them again. The shadows should look smoother after that.