Unless you don't mind a hostile take-over don't make it too permissive though. GPL is a good license if you want good protection while still allowing people to fork, share and profit on your work.
Are there any stories/examples of MIT-licensed projects being subject to hostile take-overs?
Also if it's you are the originator of a project what's stopping you from using the GPL license but not disclosing your own source while you commercialize?
Or companies adding closed source features to open source software. You can't do that with GPL unless you own all the code.
The classic business plan for software is to charge per license/copy. But if you release your software for free, you have to sell something else. And anyone who come up with a good solution for this will be the next unicorn.
Also if it's you are the originator of a project what's stopping you from using the GPL license but not disclosing your own source while you commercialize?