While I do agree slots are too much for totally focused PvP guilds, reducing the slots that much would affect guilds that aren’t 100% PvP oriented as normally there is a lot more demand for PvE guilds. In my opinion something like this would be a better option (I’m not 100% if it’s right), up to 50 slots player rating counts 100 percent, but if for example a guild has 60 players each player rating would count 90%.
but i don’t know how this would work with more specific numbers like 67 members, or ratings like 337. But idk, it’s just my thought