Anything that takes more than one action is a project so Yes - have a project for every file, even if the count is 100 or more. In Omnifocus, you can group similar projects into folders which may help. Also, you can add deadlines for some actions (a closing, for example). Also, you can view Next Actions by project and also by Context, which is helpful.
Thank you - the folders is the key. Otherwise, I was having a hard time imagining how I could filter out those files when I needed to see all the other balls in the air.