I say it depends on a few things, ceiling height does not look to matter as even 8 ft for your pose is actually high in my eyes.
your preference, what you like, you will look at it most,
"traffic" in room, are there taller people who may hit nose if to low, people who will "pet" touch it,
and position/pose of mount, is it full, semi sneak, your awesome ram looks to me like it would "show" better if lower on wall. Somewhat lower with chaps just above those who may want to touch. Without those people mounts nose just above eye level possibly.
I have 16' end walls in my room and just mounted a SA blesbuck next to my Namibian one way up around 12'. The new mount does not have the chin down pose like the Namibian one and I am not as impressed with how it looks up there. Will probably remount in a lower spot.
If you have someone who can hold your sheep in a place you want, then you step back and look. If you like perfect, if not, up, down, left or right until you get what you like before anchor is installed is best way.
When I finished my room I went to the Brick and took fridge cardboard, cut out life size 2D pics of all mounts then stuck to wall before any hole was made. Worked for a single guy.
MB