However, they suffer from the same flaw as round-robin tournaments: once a player/team starts losing a bunch, they have no motivation to continue playing. They know they can't win, yet they could still have a whole bunch of meaningless games in front of them. This is fine when playing with pre-arranged people (either your friends, or a group of top players that are trying to determine who is best.) But doesn't make as much sense for coin tournaments, as the goal with those is to try to get 1st/2nd to get the coin prize, and once that goal is no longer attainable you don't care about the tournament anymore.
When organizing coin tournaments you can be sure we would arrange multiple seasons and certain conditions, so being the bottom 2 teams means relegation and having to go through the entire hard process of making it back to the swiss phase.
Think LCS for League of Legends:
You do challenger double elims/single elims in order to qualify for 2 positions in a regional swiss/RR, the rest would be invited or be in based on their past record. From the regional RRs you go into a World Tournament which honestly could be anything from swiss, RR, DE, but definitely not SE.
So understand that swiss/RR formats should mostly be an inbetween tournament for the final coin tournament. I think people who host events would love to play with this option.
Allowing host to set seeds is easily abusable. I guarantee you that we'd see a ton of tournaments where all of the good players are on one side, and all of the poorer players and the tournament host are on the other. That way the host can get a "free ride" to the championship. Even more, it's hard to police this kind of thing, since I don't know of a way to clearly define a rule that outlaws it. Frequent players can spot this and avoid that tournament, but then it just becomes a newbie trap since new players won't know enough to spot it.
How about coding a way to set seeds for certain events that you know won't try to trap newbs and the host isn't playing in? In competitive brackets it's not 100% necessary but it definitely helps from a broadcast perspective. When I broadcast or host an event I want it to be as enjoyable to the viewers as possible, if the pros are spread out based on seeds I can ensure that some interesting upsets will happen and that the action progresses to the final.
We could come up with some sort of 'broadcaster' status for Warlight. People who broadcast on Twitch or Azubu or Youtube are granted broadcaster rights, and can keep them so long as they don't abuse these rights. This way they can set up seeds.