David Johnson worries

Would you give up DJohnson for a lower end RB plus someone else or keep what you have?
Rb: D Johnson, Carson, D Montgomery, L Murray and K Ballage
WR: ODell Beckham, R Woods, r Anderson, D Jackson
We are a 2Rb, 3wr and flex full ppr. Thoughts? I might be able to swing T Hill and M Samders?