It’s been blatantly obvious that the Mavericks' two biggest needs are a big - despite having a roster full of them - and a ball handler/playmaker in addition to the emergence of Bruson. There have been discussions on Twitter, podcasts, and blogs about which need is greater. But their biggest need may actually be a "been there, done that" veteran who can play 20-25 min a game and be there late in games to help close-out close ones.
Names could be thrown out, Goran Dragic for instance, but perhaps the Mavs best bet would be someone like Rondo ("BLASPHEMER!" you may be shouting) was on the Lakers a couple of years ago. Although the Mavs do have multiple players around 30 who have been in the league for many years, it is odd how little of a vet presence they truly have. Tim Hardaway, Jr., Trey Burke, and Reggie Bullock have spent the most time in the league at 8 years each, but those years do not bring much playoff experience. Most of it was gained in the last two years. THJ, Boban, Burke, and Bullock all had some playoff experience prior to joining the Mavs (15, 18, 9, and 3 games respectively), but for the most part, the time they played was limited.
Another important factor to point out is that most of the roster has very little experience winning. Not just finishing the season with a winning record, but being a top seed, advancing past the first round, etc. Ex-players on NBA TV and NBA Radio often talk about players needing to learn how to win. It’s making the right play at the right time late in games, scoring when it matters, setting up teammates, etc. For instance, how many times the last several years and continuing into this season have we seen the Mavs cough up a late lead and blow the game? Recent examples that spring to mind are December 7th vs the Nets where they blew a 17 point lead in the fourth quarter and wound up losing by 3 and the Lakers game on December 15th.
The Mavs need a legitimate veteran who has experience winning during the regular season and in the playoffs. While the Mavs are not going to get a player like Chris Paul, it is important to note what he has done for a very young Suns team. There are veteran players to be had, either through trades or via the buyout market, but the Mavericks desperately need veteran leadership and they should seek to get it sooner than later. They did, however, try to do something like that when they traded for JJ Redick last season. That may not have worked out, but it does demonstrate that a savvy trade could be done even with few assets.