This tournament form does not work too well. Take a table with three highest rated players in each group and you will find:
League 1 : 1k 1k 2k
League 2 G1: 1k 6k 12k
League 2 G2: 1k 11k 13k
League 3 G1: 4k 5k 9k
League 3 G2: 3k 4k 4k
League 3 G3: 13k 19k 19k
League 3 G4: 4k 9k 9k
I find this rather unbalanced. Since only one player drops down from a league it will take ages fro this to level out and new strong players will start at the bottom.
Since a ch.ship round takes months even for 9x9 this will be even worse on 19x19.
I think your wrong, or rather I hope so. In fact the first 2 of each league advance to a higher class. So normally there should be at least 4 people falling down to the lower league. The trouble is that new people (i.e. people subscribing after a round is started automatically are added in hte lowest league) you could say that there is a certain benefit for players that keep playing here. On the other hand, I (as a bad player) might keep on losing games, because I don't go down fast enough. I think it is better to see what happens, and then ask maybe for some changes
One problem is how players change between leagues. It might work OK in Go9x9 when played awhile. I am quite certain that in 19x19 it will not work too well because of the length of the game. You must expect one round to lst at least 6 months, probably longer.
The other problem is how League 3 is grouped. 1 group is MUCH weaker than the other 3.