I'm not sure I understand your reasoning here. Why does Devin Booker need essentially an all star PG next to him? A PG that can pass, defend and shoot. Hell, every team wants that. Devin Booker has one big weakness and it's defense. Rubio is by far a better passer and defender so you let him control the ball and defend the lead guard and you let Booker play more of an expanded Buddy Hield role and concentrate on scoring more efficiently. Booker still has a ton of room to improve but your lead ball handler getting 6.8 assists and 4.1 turnovers a game isn't going to win you very many games. Something had to change there.
The issue is does Booker want to be Buddy Hield like on offense? You’re talking about a guy who is 8th in the league in usage rate. Higher than Giannis who was MVP and higher than Lebron. Note that I never mentioned defense as an issue and in fact I used it as a strength in my previous post. Rubio will help on defense for sure, he’s a savvy vet.
Rubio is around the top 100 for usage rate himself and his greatest strength on offense is passing, which directly influences Booker’s game who needs the ball pretty much all the time. You would be asking Booker to completely change who he is as a player to accommodate Ricky Rubio. Think about that. One of the best scorers in the league giving up the rock to accommodate an aging Rubio whose style is being quickly rendered almost useless. Rubio went to the Suns because no one wants him. Rondo (similar type of style) is only on the Lakers because they have no money to pay anyone that’s better. Both would be in a far less prominent role if the Lakers had money and if the Suns were any good/smarter. The Suns would have been smarter getting a 3 and D point guard that can pass the ball decently and knows his role rather than a guy who needs to ball to be of any service on offense.
I’ll tell you right now what’s going to happen in the regular season. They will take turns sharing the rock initially and I’m sure there will be some good possessions, but eventually the alpha dog Booker is going to command the ball more especially in late game scenarios. Rubio isn’t remotely a threat to shoot the ball so his defender will instantly go to double Booker without really losing any sleep leaving Rubio open. Booker will then have a choice. Shoot or pass to bricklayer Rubio? Once teams begin to constantly double or triple team Booker, it will be obvious that Rubio’s strengths simply do not outweigh his inability to shoot.
Rubio is a good and smart player and he will definitely help them in some areas, particularly defense, but he is nowhere near a natural fit to Booker. They needed a guy who can shoot spot up threes and move the ball around when needed on offense but generally stays out of the way. Instead they signed a guy who needs the ball to be effective on offense and paired him with a guy who never lets go of it. Great idea!