Possible choices:
Show films in your digital room around a particular theme, country, genre or director. Retrospectives, live interviews, Q&As with filmmakers and lectures also lend themselves to virtual cinema. Also decide how broad your offering will be: do you curate films (as Picl and Mubi do) or offer a broader catalog (think of The Criterion Channel)?
Programme films that provide depth or broaden the physical offer. Think of a documentary about a director whose latest film runs in physical cinema. You can also extend the lifespan of regular releases online, by screening films that are no longer running in physical cinemas.
A digital platform lends itself ideally to extending the screening window. For instance, you can continue screening films online after they have disappeared from physical theatres. You can also give older films or recordings (of talks or events for example) a rerun online.
With virtual cinema, you can make physical film festivals and events accessible to online visitors, but organizing specific online events is also possible. Think about lectures, debates and one-off film screenings. You can also choose to livestream existing offerings, concerts and screenings.