I get what you're saying in regards to assets being a bit hard to change for existing characters. I see both sides here and I don't think they are being outright hateful, just very critical due to the argument you gave considering the fantasy races are there. Personally the character I thought was black was the guy who sells you weapons but I can see their point: no truly ebony skinned characters. I think if you ever planned on throwing another character in in some way down the line it's something to consider. As for Asians it's not toooo much of a stretch to have a Mongolian character, considering they went as far as Poland and defeated Templars there during the height of their empire. I can easily envision a hot bearded Mongolian-esque guy who has an archery or horseback related job in your game. Backstory could be as simple as him wanting to escape participating in the brutality of their warfare and travelled far as he could running away. I assume you've got all your characters done already though. But if you can squeeze in another character or two though, representation is good for sales and it'll make bara enthusiasts of all colors feel welcome in wheelcum.
Bara isn't necessarily only the extremely muscular body type, it's just typically masculine. Mainly anything that's not femme guys drawn by women for women, which is what yaoi is. That 'masculine' body can be anything from an otter, a muscle-fat bear, purely muscular guy, or even a chub. I think there's diversity here in your game it's just that one specific body type (purely muscular) that's most common in the game is a very noticeable majority, like 70 to 80% if I had to guesstimate. Daddy Orc is probably my favorite to fight or see in the scenes because he actually has a bigger belly and fatter ass but he feels like an exception alongside the bear baker and the beer guzzling fella with the axe game.