Depends on how vindictive Abbott is, which is a hard guess. He worked so hard in unconstructive criticism to become Prime Minister and then showed that he didn't know what to do when he got it.

Julie Bishop, who is nicknamed 'the cockroach' due to her ability to survive as deputy under multiple leaders, is sometimes raised as a possibility but I don't know whether she wants the top job.

Morrison is considered a possibility and had the 'advantage' of being loathed by the left, having taken a hardline on both asylum seekers and welfare recipients. I don't know what his internal party skills are like.

Much depends on whether Turnbull is as uninspiring as he when he was leader of the opposition.