Hopfully this will be implemented soon
then we will have those 2, 3 seconds insta plays and no gdrive bans.
As for direct streams probably 100+ easy until you hit your bandwith limit of 1GBps and even if rclone eats all ram with 1G buffer it will be swaped on disk so it should still work.
My setup for plex server is
2x xeon e2670 ( 32 threads )
2x 512GB SSD in strip ( one dies and bye bye os )
4x 2TB in raid 5