If only there was a middle man system to prevent that. For example, you go to a NPC and request a trade with that person and they can accept, and then you can put the mesos and they put the item, and has to be accepted by both players, but the NPC can hold 2.1+b so you can go put mesos in the storage or on a mule, and go back and accept more mesos.
I'd much rather see some sorts of vouches/tickets that can be traded in at an npc for x amount of mesos. Having a 1B or 100m ticket to buy stuff with instead of changing the meso value. (Also remove taxes, cuz their uneccesary.) And when u speak of drastic changes, whats to stop you from changing the current mesos cap, why do u keep it at 2.1b?
Taxes is to stop inflation. There is a reason for that number, it's the maximum limit for 32-bit integer. That discussion about having such an item to trade for mesos has been had several times, including in this thread.
One good solution could be drastically increasing taxes (double the current amount or w.e),this would reduce inflation and make more trades possible within the 2.1b mesos limit.