1. Any basic parameters on the types of stories I should submit if you approve my joining your publication?

Write something awesome.

2. Also, if I am approved, will E3 simply pop up as an option when I go to the publishing screen for a story?

That's you added as a writer. Welcome ;-)

E3 will pop up as an option.

E3 is not a reading club, however, it would be nice if every author subscribed to the publication and read the stories that catch their interest. I find this engagement is reciprocated.

Wishing you all the best

Malky