Is there a specific reason MAX_REQUEST_SIZE for claiming is limited to 25 in ServerClaimsManager? Could this maybe be configurable?

Making bigger claims is unfortunately rather cumbersome this way.

It's limited without a config option because a high enough limit makes it pretty easy for any player to overwhelm the server. Most people would not set it to as low as 25 if they had the option, they would set it to 1000+ or something, which would make it take quite some time to process larger claims in a single tick. Each claim needs to be added to a compressed storage and also synced to every online player. Setting it to as low as 25 might have been a bit of an overkill though. I think I just found it to be a good starting point, to see if anyone asks for it to be increased.

That being said, I can now use a similar method to that which handles sub-claim deletion, spreading the work across multiple ticks if necessary. I think that is what I'm going to do and add a config option for the limit, in case someone still wants it for balancing purposes.