Can they breathe? Blink? Tuck a jersey in? Tie a bootlace? Huddle to regroup and revamp tactics? I believe all of these to be very common indeed - so common that a referee awarding a retake of a missed conversion would be viewed as not only plain wrong, but also barking mad. Why then would it be right to do the same for leaning against the post?
I support only dealing with 'actual' kicker distractions, not every theoretical one, as per your list.
I'm just showing you that yes, as per law kneeling down tying shoelaces isn't actually permitted ( although standing & doing the same might be a debate lawyers to earn from) ....although I'd argue that breathing is an 'implied' condition of participation
In the old days you could easily wobble a post, 10m+ further up its a potential distraction to the kicker.
Plus the risk of wobbling them may topple them ( remember CamborneWindyPostsGate) !
My Welsh Rugby teacher (evangelist) always said they were to be untouched when a kick attempted, I doubt he made it up though.