1. Defensive-oriented lengthy wing
The Dallas Mavericks' biggest need is adding a bigger-bodied lengthy defensive wing to slide into their starting lineup. Grant Williams hasn't played as well as expected over the last 15-20 games for Dallas and it has severely hindered the potential of Dallas' defense. Williams has lots of time to still be a positive contributor for Dallas but he hasn't followed suit on high expectations after a hot start to the season shooting the ball.
Williams can be serviceable for Dallas off the bench if his shooting trends in the right direction going forward, but his inability to consistently guard some of the league's elite bigger wings has hurt Dallas' defense. Having an elite defensive wing who can help aid the low man but also defend the perimeter would be a huge addition to the Mavericks' defense, as Dallas currently doesn't have any player with that sort of combination of size and athleticism.
There aren't many players in the league who fit this sort of mold, but that is why they are so highly coveted. Dallas had a player of this sort of mold in Dorian Finney-Smith before he was traded to the Brooklyn Nets in the Kyrie Irving deal last February, but has lacked a wing of such caliber since. Derrick Jones Jr. has been great defensively for Dallas on the wing, but he's more curated to guard smaller wings and guards given his thinner frame.
Dallas has been rumored to potentially be targeting Finney-Smith again, as trading for Finney-Smith or another lengthier starting-caliber 3-and-D wing would likely thrust Dallas into the sphere of contender status. Trading for a sure-fire starting four would hopefully remediate the need for another center for Dallas because they'd have an abundance of wings at that point, but they'd have to make sure they get a wing who can rebound if that's the route they choose to take.
For more on the Dallas Mavericks and what they'll do during this trade season, stay tuned with us as we'll have you covered.