Please don't make this open source. It'll end up in the vast graveyard with all the other open source projects that went no where. How are you going to sustain development, make it better, hire designers, make a living if you just give it away for free. You are not Mozilla, Oracle, Google, Automattic. They make money in various ways which is how they can support development of their open source software. You don't.

Don't be afraid of asking for money and becoming successful.