Just saw this here:

http://www.cultofmac.com/311452/photoshop-gets-new-challenger-os-x-looks-great/

and here:

http://www.techradar.com/news/photography-video-capture/cameras/serif-s-new-mac-based-photoshop-rival-is-now-a-free-beta-1283949

I love seeing more competition in this area. It’s great for the end user. Not sure how this play into working with Photos … but can you imagine a non-destructive workflow using such options with Photos as the hub … this could easily answer the absence of brushes for one.

direct link to the developer’s site if you are interested in becoming a tester:

https://affinity.serif.com/en-gb/photo/?source=USwebgains&siteid=73669&IsoCode=US&culture=en&&MC=WBGSER02

I am in no way affiliated with the developer (or Apple) simply sharing information for discussion and consideration. The same developer has recently offered an alternate option graphic design that competes directly with Illustrator and seems to have very positive reviews.