Why event organization? are you already familiar with each piece in that list? Why that tech stack? Do you need to care about scaling or is self hosting more fun for this?
The distinct concept might be to take that stack and do something else with scheduling? I think weaving in a thing you like or want to specialize in would be better than a generic scheduling app (I don’t know those apps you mentioned).
If you’re doing a web app focus then the MongoDB INSERTS and updates will be easy to template once you find how they communicate. The DB should do less of the logic and just hold your “primative” data that can’t be calculated. It might even do BLOBs if you want to skip a cloud bucket because you won’t have to scale…
Good luck!
Ton (imperial) is 2000lb vs tonne (metric)