It doesn't improve us enough immediately to make it worth killing our future flexibility. Rather continue to develop Barnes and hope he can make a bigger impact towards the end of the season and in the playoffs. Lotta games left. And I think Barnes can be a Gay level scorer worth better defense down the line.
Now Barnes for Batum I'd do. Not sure if Portland would though, but they could look to flip Aldridge also and go with a new very young core of Lillard-Barnes-Leonard and whoever they get for Aldridge, which would likely be on the Lillard/Barnes level.
I'd also consider Barnes for Iggy. A little worried about his age with past injuries, but he'd be such a great fit i think I'd take my chances and hope Bogut gets back healthy. Curry-Klay-Iggy-Lee-Bogut would be a very, very good and balanced starting 5.