I had never to use "!g" before. Now it is required for 1/3 of my regular searches, and "!ig" for 100% of the image "!i" searches.
I replaced 90% of my images searches with Bing Images. I like the UI better and the results are almost as good. Since I use DDG for ~80% of regular searches and Google for the remainder, not giving one party all information seems like it should somewhat level the playing field.
Also, I was going to type that a small percentage of my image searches still go to Google for their license selection feature, but I figured I should double check, and whaddayaknow? Bing can do license filtering too. Not sure how good it'll be, but I'll definitely be trying this.
Note that instead of typing !something (which I find quite annoying), you can just bind your browser to a keyword. I type "bi test" in my address bar for Bing Images "test" search, instead of having to type a bang and some by-ddg-defined shortcut and giving DDG the data (not that I distrust them, but need-to-know...). Wiki searching is also super convenient like this: wi for wikipedia, dwi for deutsch wikipedia, owi for openstreetmap wiki, etc. Right click in the search field and choose 'Add keyword for this search' usually does the trick.