The main thing I see that is holding the Suns back from being a powerhouse is their defense - lack of length. Even on the last few baskets, you can tell that Allen just isn't long enough to make strong contests. We have length/size with Durant/Nurk inside. But we lack length on the perimeter. You need length on the perimeter to challenge shots. We have smalls - Gordon, Allen, Book all playing the 3/2/1.
This is a roster thing. Did not build a roster with a legit starting level 3. While Allen/Gordon are starting worthy, they are basically 2s. We need a starting level 3, who fits in with Beal/Book/Durant/Nurk. No one earth shattering, just a player that can give you those needed shot challenging on defense, and decent enough offense that he is playing around those 4.
I feel if James Jones makes just one move like that, we have Beal back too, then we're going to be there and be able to beat the top teams in the West. One of the biggest problems is that Vogel can't really put forth an effective consistent defense without that length. You can see it in our execution. We're missing that length on the perimeter.