Fun things to do in X-Plane:
Land a 747 on an aircraft carrier
Get in an X-15, drop from a B-52 above Idaho and do a boost to 350,000 feet, re-enter over southern california and do energy management to land at Edwards Air Force base.
In an XB-70, blast across the Baltic at just under Mach 3 about 20 feet above the ocean, cross into the gulf of Finland and turn in towards Moscow, staying below radar...
Take an F-35 JSF, Marine version at LAX, and do vertical take off. Hover on the thrust, then transition to forward flight, then transition back to hover over downtown LA and land on a helipad without falling off the building into traffic.
Take an Osprey from Santa Monica municipal to San Francisco, doing a low pass under the Golden Gate, maybe landing at Alcatraz why not.
I enjoy doing suborbital hops from LAX to Sea-Tac in the National Aerospace Plane that was cancelled during the 1980s, precision helicopter flying.
One very cool thing in X-Plane you can't do in MSFS is a full simulated Shuttle Re-entry from orbit, with real energy management consoles and apparently realistic handling.