Why not give the full version of Photoshop a try? As mentioned above it already handles 200% display element scaling.
The Creative Cloud program offers a subscription for $9.99 / month for Photoshop and Lightroom. I don't know how often you have been updating your software nor how much you've had to pay, but this isn't a bad deal as compared to past license upgrade costs for Photoshop alone.
Creative Cloud free trial & plans : Adobe Creative Cloud
-Noel