My community (and me) mostly use the "Shuffle Seed" botton, when we host a tournament with no signup page; the tournament hosters manually add all the players, then they press shuffle.
And that's ok!

Now, you introduced an automatic way to join the tournament: set a beginning date and time, then add the possibility to check in.
That's wonderful! Players can automatically join (no need for a tournament hoster that has to add manually the nicknames).
But then? When time is up, we need a hoster to start the tournament.
Can't you avoid this? When check in time is over, Tournament should automatically start (or just let us choose: "[_] Automatically start tournament after check in").
HERE COMES THE MOST IMPORTANT PART OF THIS PURPOSE:
Please, add the chance to seed players randomly!
Actually the first joining is the top seed; if we choose "traditional seeding method", the second joining is also top seed (2nd place obv). If we choose "the order of the bracket", the second player joining will face the first one.
Is it possibile to let players joining AND set them in a random position?
This will be a lot useful in case of auto-starting tournament (as purposed first in this page).

Abry