3/5 3S is the shit.
JoJo’s Bizarre Adventure uses 3/5 most of the time. It gives Mariah a better chance to compete due to her level up system and her being the weakest character in the game anyway. She pretty much becomes playable when hitting a high level through her magnets. Also makes the Dio/Jotaro Time stop instant kill bug more likely 
On a related note, meter carry over between rounds can affect win chances, i.e. some character may have a better chance at winning in later rounds when they have meter (heck, doesn’t SCV give meter to whoever lost the previous round). This could possibly have an affect on peoples chances of winning a game depending on how many rounds it has.
I’m not sure what to make of single elimination tournaments so bad. hell i never even understood bracket resets but I guess that’s how things handle with no changing.
I never played in tournament formats or with “first to” sets with my gatherings. But I do fundamentally believe 3/5 is good round system.
SCV gives meter to the losing person when their opponent is on game point. So if your opponent has beaten you two rounds (SCV default is 3/5), you get one meter.
Easier to get randomed out in single elims. That said, they also help lower tiered characters reach further.
Single elim has the problem that it only produces a meaningful result when properly seeded, and to properly seed, you have to already have a good idea of the relative skill levels of the players - if not properly seeded, many players will actually wind up eliminated earlier than their skill would suggest.
“Bracket resets” are a result of a tournament being double elimination: to be eliminated from the tournament, you have to lose two matches. By definition, grand finals consists of one player who has lost one match, and one player who hasn’t lost any. The player coming from the winners bracket only has to win one match, because that is the other player’s second loss, which eliminates them. The player coming from losers, however, has to win two matches to win the tournament; the first, to knock the other player into the losers bracket (this is the “bracket reset”), and the second to eliminate them.
PL was complaining about the one round matches because the stage transition on the bridge level did massive damage, which just turned the fight into whoever knocks the other player off of the bridge wins.