Not sure about Locky and coaching anyway, sure tactically he will have tricks in the bag, but obviously there is so much more to it, even then, when his time comes the game may have once again changed in the way its played and what-have-you. If I was him, I'd go start a family and live a good life with the wealth he surely has, until he's ready to commit to rugby league again.
On the other hand, It could possibly benefit to coach straight away, so he can coach players he has played with, which could benefit him in years to come if he chooses the coaching career.
Chumba: I'm sure Origin coaching is a different party all together. It resolves around getting elite players to play well together over such a short period of time. (Of course, QLD generally stick to the same Squad for a number of years until change is needed) I agree club coaching is more elite, but origin coaching would be a different tangent.
Henjak, Even though it may feel like the Broncos resorted to him because they could not get Henry or Bellamy, I'm sure Henjak understands how how profile coaching the Broncos is, I'm sure he does not mind being the 3rd choice, and will try his best for the Broncos to succeed. I'm sure its similar to many things, much like being a second choice Quarter back or something, if you're called upon in a time of need, you don't think twice about pride, you grab your opportunity with both hands and have a dig.