I would say definitely have the skull cleaned.You could get the hide tanned and hang it on the wall,throw over the back of a couch or railing.
The cheapest mount would probably be a shoulder mount for the wall with a closed mouth.
Don't forget framed pictures if you have a good one.
I have a customer that has a large blow up of his kill photo framed and matted.In the lower part of the mat,below the picture itself,There is a long cutout in the mat and the actual arrow is there.It is beautiful.
Maybe someday I could get a picture of it.