I would love nothing more than to see Baynes take Luka off of his feet on a hard screen. I'm not sure how some people on the board would respond to that, if it happens. Baynes has quickly become a favorite Sun and Luka is a lot of poster's favorite player that isn't a Sun.
This might be the most understated aspect of what he offers to this team: Baynes lays the wood.
Since he's been gone, I've noticed we take less charges and commit less hard fouls. Good basketball has an underappreciated aspect of "punishment in the paint". Baynes offers that and this team has sorely missed it. When you come into our paint, with Baynes, you will pay (either by committing a charge or by taking an elbow to the throat). Smaller, weaker players are going to naturally become less aggressive attacking the basket when this occurs. This day and age is full of weak players who don't know what to do when they get punched in the mouth. This gives us a tremendous advantage.
On top of that Baynes offers some old school aspects:
He takes charges.
He's masterful at screens.
He sends messages with his physicality.
He annoys opposing players and gets in their head.
He energizes teammates (and fans).
He gives wing defenders confidence to work hard and stay aggressive because he has their backs.
Throw in the "new school" aspect that he hits three's and you have a "glue player" that does all the little things to help you win.
One other addition of note on Baynes. My wife hates the NBA. (Partly because of the fixed Spurs/Suns Game 3 atrocity in 2007, and partly because it's full of a bunch of whiny wusses.) This year, before Baynes got hurt, she was glued to the set. I've never seen her this interested in basketball. My guess is that she will watch tonight with renewed interest. It got me thinking; I wonder how many other people are turned off because of the lack of physicality in today's game.