Summary
Ellington's one NBA skill is outside shooting, as the overwhelming majority of his field goal attempts come from beyond the three point line. Ellington can not only hit spot up threes, he's great off the catch and needs little room to get his shot off. He shot 42% from three in '20-'21 on high volume, but that dipped to 38% in '21-'22, and overall Ellington was not been able to make a positive impact on the Lakers.

Ellington is fairly one-dimensional. If he is not hitting shots, he's not contributing in other ways to compensate. I have always had a higher opinion of Ellington than the league does, and that was clearly evidenced through Ellington settling for minimum contracts in recent years. However, I think I've given up on him being a rotation-level player.

I stated last year that I wanted to see Ellington on a more competitive team, and that theoretically came to fruition when he signed with the Lakers. However, after starting some games early Ellington fell out of the rotation, and was just one of many aspects of the Lakers' season that was disappointing.
 
Cap Considerations
Ellington will be an unrestricted free agent with a $1.8 million cap hold and Non-Bird Rights. This means that the highest starting salary the Lakers could offer him using the Non-Bird Exception is $3.4 million. This should be enough to retain Ellington, since he settled for the minimum of $2.6 million to come to Los Angeles. Alternatively, the Lakers could use their Taxpayer Mid-Level Exception to re-sign Ellington if he demands more than $3.4 million. 

Other teams will have multiple ways to sign Ellington as even teams without cap space could possibly use any of the Non-Taxpayer MLE, Taxpayer MLE, or possibly even the Room MLE or Bi-Annual Exception to sign him. It's also likely that Ellington only gets minimum offers, and he may not even get fully-guaranteed offers.