I'm a huge fan of Phocus's simplicity versus many other programs. The one thing I've always found limiting was the ability to us keyboard keys to bump adjustments in the adjustment panel. For instance in Lightroom you can use programs like Motibodo to use quick key adjustments. I get that many people shooting in a studio environment stick to a lighting setup and can nail everything shot to shot. I'm a portrait and headshot photographer and many times I'm moving my light or the subject is moving and exposure can shift the slightest bit. Also shooting in outdoor environments where the light is changing constantly. The frustration is that for any frame that needs adjustment you must use your mouse and or type in the number you'd like and then move on. Sure you can use the modify option for a selection of images, but again you can run into the issue of any number of shots needing more or less adjustments. It would be fantastic is you could assign keys on the keyboard to bump exposure, contrast, recovery ect...
The one other thing to better the new adjustment layer features would be the ability to adjust the size of the brush via the keyboard.
I truly believe those 2 things would bring Phocus to a level that would eliminate the need for a lot of the adjustment that one might do in PS.