if you would prefer to write some original software to your own specification, thoroughly test it, get it verified everywhere, create an original web interface for it, and then give that away for free then that's entirely your choice and I fully support your efforts and wish you luck.
Well, i read the code, the owner has way too much power. Such short code and simple website doesn't justify a 50% fee. Well okay it is an experiment right, it was your idea yes.
But don't make this look like a wonderful and impressive work, there is some simple functions, there is not much to do after registration and the website isn't particulary great. I don't think it is a matter of subjectivity, just a look around and you see everything.
Good luck.