I hope it's not Partridge because that would be too obvious. To make him a main character in just one episode and to blatantly be an ass in that episode without his character going anywhere just seems too obvious. I would be extremely disappointed with the creativity of the writers if this was so. Malcolm McDowell's character would also be a let down, personally.
Jane's father would be a bit better, but I would hope that there is some creative solution down the line with a character that we have yet to be introduced to. Obviously with enough clever writing and creative storytelling or creative writing and clever storytelling, any of the above possibilities could turn out great. I just hope that will be the case if and when the time comes.