So it sounds like you're convinced you should aim lower, but are having trouble actually doing it.

Oh no, you don't ask for feedback from your colleagues - you get it from people with the problem you're solving. From users. Your fellow developers can't even know if you solved the user problem; the best they can do is point out things like grammatical errors which, as you say, is useless.

EDIT I guess your PHP friend wouldn't have been able to bring over users for his very his first app, and I bet he remembers it vividly. You could email him, or talk on the phone. He's not the only person in the world to have shipped, but you know him, so he's an excellent person to start with. You could visit him. Consider: 500 km vs. 4 weeks. Sounds ridiculous, but if you take this journey, you won't forget his point of view.