Extent of injury will always be taken into account for length of suspension, it is part of their guidelines in setting ban length.
It isn't part of the decision on whether the act meets the RC threshold though (and shouldn't be). The Law is there to remove the act and prevent a possible bad outcome.
My argument on this case is simple. Did Hooper strike another player? Yes. Was it serious enough to warrant further punishment? IMO yes, it had a high risk of injuring the player. Are there mitigating factors? Yes, it was instinctive retaliation and Hooper has an unblemished record so hasn't shown a propensity for violent acts before.
The only tricky part is the usual tangle the judiciary gets in when setting a meaningful punishment. Unless they can get some concrete assurity that he was scheduled to play this weekend for a club side, then any ban should not count that game.
I would think 1 week (being the Bled game) is fair and reasonable punishment, which is a bugger because Pocock is a better player.