Brilliant idea. A draft is meant to go hand in hand with a cap.
The two problems naysayers come up with is tanking and there being no motive for clubs to put money into juniors.
Tanking:
The solution is simple, a lottery. Picks 9-16 are given to the top 8 teams as is when the regular season is finished.
But picks 1-8 are given via the lottery. The non top 8 teams all have a chance at getting the #1 pick. The woodern spooners have about a 25% chance, and then decreasing until you get to 9th place.
Simple solution, the lower end teams have a better chance but the possibility of tanking is reduced.
As for juniors, like is suggested in the article and along the lines of the AFL's father-son rule. Each club has 1 or 2 designated junior picks where if one of their juniors has been picked ahead of their turn, and if they want him, they can claim him and their next pick is automatically used on that player.
For example, Penrith has the #5 pick. Easts has the #3 pick. Easts picks Westie Bogan, Penrith exercises the rule, their pick is used on the aforementioned Bogan, Easts has to pick again.
Another advantage of the draft is that the buildup to the draft and then the draft itself will help keep the game in the headlines for a period in the offseason. That kind of free publicity is very valuable.