I do disagree on ending with that team hero shot. The right ending is a different hero shot, right before The Knightmare, with ironically the same last shot as the theatrical cut, of Clark opening his shirt to reveal the traditional Superman suit being back.
The rest of the epilogue is fine, Barry getting the crime lab job, Cyborg finally feeling comfortable in his own "skin", Bruce and Diana setting up the team headquarters, MARTHA?!? getting the house back via Bruce, etc.
I'd go with Lex and Deathstroke as the mid-credits scene, with The Knightmare as a cut scene for the extras that ultimately has no place in a three hour type cut of the film. It's there as a teaser for a film we never got and will never get, where Darkseid wins for the first part.