Perhaps make it only visible for allies? But more realistic that way. Also, being able to see absolutely everyone's debts might be exploitable somehow. I'm not sure how yet, but it feels like it.
I would agree with this... if only a host of other sensitive information was not already openly available (e.g., land troops, naval size, economic information etc). These sort of information should only be obtainable through covert actions or such, not openly available to everyone IMO.