When I first started out I got WAY into a starter and wrote about 10k? In fairness that was setting up an entire world/plot but it was a mess and I felt pretty guilty for writing so much.
I think set roles that leave room for interpretation could work. If you wanted mystery then as long as you have a solid plot and have players who are fine following your lead it should work. As long as you pitch it all clearly/set expectations you shoukf be fine with getting people down for...
I think depending on the plotline or route you wanted to go it would be completely possible to do a RP similar to those. It would just need some collaboration in regards to the plot/characters
For me it's more so down to the character? I'm not that fussed about specifically playing xy or z characters. If I have an idea for a male character I do that, female then I do that? I'm not that fussed