The head shape is probably more referring to like golden ratio and silver ratio faces, like how western art has more rectangle shape where things like chibi has more round.
I don't agree with the 'dwarfs dont exsist so theres no reason for a standard'. Firstly dwarfs do exsist, they look different to fantasy dwarfs but that doesn't stop them from exsisting (looks rather bad that you just completely disregard their exsistance). Secondly you can have diversity within a standard. First one that comes to mind that fits all the requirements is 'Tusks: the orc dating sim' (https://hxovax.itch.io/orc-dating-sim). Orcs don't exsist but there is a standard and you can have diversity within that standard. You can't just do something like draw a goblin and say its a dwarf and when someone points out that its a goblin just say dwarfs don't exsist, there's no standard it's just a swamp dwarf. Just being a dwarf dating sim already sets a standard that people will think of and will draw people who are intrested in that standard, just disregarding that seems more of a bait and switch.