he projects to be around a 4 offensive WAR player over the next few years. Fangraphs has a WAR valued at around $10 million, so $30 million a year or so doesn't seem to be out of line with his value. at least on offense. The gamble is that his 2018 -3.2 dWAR is an outlier (previous years he was around a 0 dWAR player).
Shift him back into RF, have Robles in CF, and his dWAR should improve. So its $30-35 million a year for 4 wins versus Adam Eaton at $10 million. Eaton was a 1.8 WAR player in 2018, 0.9 in 17, and around a 4.5 WAR player from 2014-2016.
2012, 2015, and 2017
Murph, Rendon, Turner, Ramos, ESPINOSA, Max, Roark, Stras, Ross, and Treinen were better in 2016, he was tied with Kelley for 11th best on the team. Max, Gio, Stras, and Rendon all had higher WAR in 2017, he was fifth best. Max, Roark, Stras, Doo, HELL, GIO, Rendon, Turner, and Soto were better in 2018, he was tied with Zim, Grace, and Holland for tenth best.
So we are going to pay LaBron James money to a guy who hasn't been in the top four on his own team over the past three seasons. I get that 2015 he was the best player in baseball, but that is getting to be a long time ago. (Plus he has a crap attitude.)