Hello! Here are some quick ideas that could become something in the future, maybe
Thargoid Prep/Hunting
Winged Conflict Zone combat
Painite mining session/Prep
LTD mining prep/session
Winged Bounty hunting
Engineering day (Farming mats, visiting and unlocking guardian zones, etc)
Artifact exploration (We can just visit cool lore-related places in the galaxy placed by Frontier for funs)
Most of the content can be done without the expansion for those who don't have it. I also liked the heelping damaged stations idea @Kriege7 mentioned, since its something i've never done before.