Best I can piece together, this should be the order of Stern games through the end of 2019.
Fall 2018 - Munsters. This is currently the worst kept secret in Pinball
Winter 2019 - Beatles. Not 100%, but the rumors are strong on this one.
Summer 2019 - Steve Ritchie's unlicensed game. Ritchie has said on more than one occasion that his next game is unlicensed, and that he's having a blast making it. Summer 2019 would be two years since Star Wars, and approximately Ritchie's turnaround time.
Fall 2019 - Elvira 3. Cassandra Peterson and Dennis Nordman revealed this game was in the works at TPF 2017, and Gomez confirmed it at TPF 2018. A fall release makes sense for this theme (ala Munsters this year) and Cassandra has also mentioned this date recently. Set phasers to kill, I think this one is a lock for next fall.
Of course, there will be a VE next year, and always the chance of a home or boutique pin as well.
What do you guys think? Solid guesses, or malarkey?