I’ve been writing on Medium for a year now. I write mostly for one publication The Daily Cuppa. The stories have to be 150 words or less. All of the Daily Cuppa writers and readers can read your article but so can the rest of Medium. You can even make your own publication and publish your own stories in it. Or just write for yourself which is what you’re doing now. Some of the publications have so many rules and requirements it’s not worth the hassle in my opinion. The advantage in joining any publication is you’ll find a loyal following in that publication. For example I write travel stories for Globetrotters so other writers who write travel will in the main be your readers too.