Last week I posted 5 things I want in ON1 Photo 10. Here's 5 more. What feature do you want most and why?

1. Editable Line Mask points: I use the Line Mask often. I want the points on the mask to be remembered and editable, like how the Masking Bugs work. You can return to a layer or filter with a Masking Bug and fine tune it at any time during your workflow. Add that same level of edibility to the Line Mask.
    
2. Luminosity Masks in Effects Presets: Luminosity masks are by their nature dynamic. Effects should record that there is a luminosity mask associated with a filter and save it as a preset. When a preset with a luminosity mask is applied, Effects can compute the mask on the fly.
   
   I understand why custom masks aren't saved in presets. They don't make sense because they will be different from photo to photo. Masking Bugs are saved in presets, although they usually need a tweak because horizon lines, subject position, etc. differ from photo to photo. 
    
3. Mask Copy & Paste Keyboard Shortcuts: C'mon... gimme this one. We've got Cmd/Ctrl-I to invert. Cmd/Ctrl-C and Cmd/Ctrl-V aren't being used for anything else in Layers or Effects. This is a small UI change for a big workflow win.
    
4. Histogram in Browse: I use Browse to do an initial cull of my photos before bringing them into Lightroom. In my style of photography, I have many photos with very similar characteristics. Sometimes, it's the same composition with slight variations to the exposure. Add the histogram view to Browse and I can make a more fine tuned selection on what photos to actually bring into Lightroom. I realize that generating a histogram might slow down Browse some, so make it an off-by-default option for the user.
    
5. Integration with iCloud/Photo Stream: I know there's PhotoVia. I took a brief look at it, but haven't had much success working with it. (I'm sure it's something I'm missing.). Assuming I get it working, I want to share photos to my other Apple devices as natively as possible. Having Photo Stream support means I can push photos to my family members without them having to know/understand a new application (a bigger challenge than one might imagine).