I don't see anything wrong with a "vehicle tag". I don't approve of "holding hands" though. A lot of those images are more or less covered by "couple", and it seems too much like the pose tag to me. Not altogether necessary.

I'm pretty sure the "jacket" tag works for jackets of any length as long as they're, you know, jackets.

Hmmm, I don't mind aircraft or ship but they wouldn't apply to many images. Perhaps a vehicle tag as others suggested.
I actually like the idea of a sidetail tag. It's a fairly unique hair style that would be easy to tag and we've already got a twintail tag too.

How about a "mirror" tag?

It wouldn't apply to many images.

"orange hair" tag? I usually use "red hair" for orange hair, but sometimes the hair is clearly not red.

"orange hair" has already been brought up and denied several times upon requests. >.<

Okay then, "nosebleed" tag?

I don't really see "nosebleed" as necessary. myself.

Neither do I. It could end up encouraging inappropriate images and we don't tend to encourage images involving blood too much.

Added the following tags:
animal suit
nosebleed
side tail
vehicle

FYI: Tag suggestions have been moved to a new thread.