The Dallas Mavericks desperately need to improve this offseason. They went just 26-56 in the 2025-26 season, their second-worst record since the start of the century, and a lot of it can be traced back to bad personnel decisions. Dallas only made three moves in the 2025 free agency: re-signing Kyrie Irving, waiving Olivier-Maxence Prosper to sign Dante Exum, and signing D'Angelo Russell. If they want to take that next step, they have to take free agency a little more seriously, signing players who can actually make an impact. While waiving and stretching Prosper's contract for the next three seasons to sign a player who wouldn't play a minute because of injuries was bad enough, it still wasn't worse than signing D'Angelo Russell while giving him a player option. It was clear that Russell's career was trending downhill. The 2024-25 season was the worst season of his career in scoring and three-point shooting.…