Same problem for me. Photoshop? Don't care, plenty of options. Lightroom? Nothing's really an adequate replacement, not least because most of the tools touted as replacements are a lot more concerned about the "digital darkroom" fucking-around-with-RAW-settings aspect that the asset management side of things.
I'm not sure your specific workflow in Lightroom, I admiditly haven't used it since 2008 I suspect. However I'd maybe suggest trying some of the other modern RAW tools, I'm personally been editing with CaptureOne as I got a serial with my Fuji camera. Usually when I want to start getting crazy with masking I'll jump into Photoshop or the likes pretty quick, personally.
Is ACDSee Photo Studio a good bet for managing metadata on video assets too, do you happen to know? I’ve been looking for a good asset manager to complement my FCPX workflow for ages, seems like a largely abandoned space on Mac.