I watched Plum in the Dleague game and the kid has a high motor, very vocal on Defense, and far different persona than Oak.
Plum has the "Please sir can I have another" ROTC/Military aspect to him and it comes out on the court. But in a good way.
He seems to very much enjoy the game. His attention to detail in his fundamentals are exceptional and for this reason I would keep him and develop him. His movements are calculated and his body core is very strong.
Not sure he is quick enough or fluid like Steve Adams. Plum is an interesting study.
As for Willy, I'd say there is a bit of Oak in him not for his "nasty", but he seems to do a lot of things well but nothing exceptional. That's not a knock btw. Today, Oak would be undersized and not athletic enough to play in todays NBA.
What is 21 year old Oak vs. 21 year old Willy? I don't know.
Willy defensively lacks the fundamentals and needs work. He is rookie, of course he does!!!!
Plum needs softer hands and more fluid offensive game. Put them together you have David Robinson!!!
Oh wait, have to do white on white, so lets say "Pau Gasol" but without the outside shot.