Barnes has done an awesome job at really changing his shot chart this season for the better and taking highly efficient shots, which has lead his efficiency to absolutely skyrocket this year.
He's really making an effort to get to the line this year .408 FTr. For comparison, James Harden is at .600 FTr (I'd wager this is by far the best all-time if the season ended tomorrow) and Giannis is a .540 Ftr. Only 12% of his FG attempts this year have come from the mid-range (10 feet-just inside the 3pt Line) and he's shooting 75% at the rim this year. Taking the USG burden off him he had his first few years in Dallas really has opened up his offensive game and him being selective with his opportunities has made him incredibly effective scoring the ball this year.
He's gotta keep attacking the rim like he has been and keep that aggressiveness getting to the FT line. When Fox and Bagley get back, having 3 guys that can draw fouls at a high rate (if he can sustain this) is such a big offensive advantage.