Handle Bar and my hands on the mew mount

[Ashbury]

and the handlebars work just fine on midlanders

It depends on your character height. The taller you make your character, the more offbase it'll be, sadly.

https://imgur.com/a/d0axt

Basically the mount seens to be scaled to your base height and does not scale with your height increase. Actually my Alt might be the lowest height possible, so maybe Miqo'tes Falcons are scaled incorrectly, since it fits her hands so well.