The current upkeep system is a dollar per chunk which can get ridiculously expensive for bigger towns and prevents towns/nations from really bordering each other. Maybe it could be 1 dollar per two or four chunks, or it could only take upkeep on certain plots which could be marked as "developed". Developed plots have to have certain blocks in their borders like crafting tables, furnaces, chests, and many more. this would allow towns to expand enough to border each other which would add some realism to the server.
Irony jokes aside with that username, the "developed" check you mentioned would just be used to claim huge areas at no cost.
This upkeep is already at an all time LOW, it has never been this low before and reducing it further to 0.5 seems dumb