It seems a continuum - screens on PW go from white to rainbow - with everywhere in between.
But yours is close to the 'rainbow' side of things.
I hate dealing with returns (and I did not return mine, which is not perfect either - but more uniform than yours) - but, in this case, it seems warranted.
The only note is - my screen got much better after 3-4 days of usage. I am not sure if it was some sort of burn-in (perhaps of glue residues?) - but my screen got progressively better over the first days. And no, it was not just me getting used to it.
So maybe waiting a couple of days might be a good idea? Unless you had the device for a while already...