Hi Alan,
being a long time Nik user (since it was NIK) and have always used it with PS (layers, smart filter), I still like it. Viveza is straight forward and CEP comes with a ton of great functions not to forget those flexible vignetting tools, darken / lighten center …
The question might be, how long you want to stay in PL’s non-destructive mode, how familiar you are with PL resp. what the application allows you to do, if it’s time to leave …
Nik SEP is still my goto tool for B&W and Nik OutputSharpener for printing from PS.
Wolfgang