Allowing you to hold more wouldn't accomplish that, though. You'd have to go through and adjust the per-difficulty awards for every quest, adjust the drops for every enemy and floor (for boxes) in every difficulty, and change the price points for selling all items in order to make Meseta more valuable. The only thing you accomplish by raising the amount you can hold is to make using a Vjaya more practical.
You can also increase the meseta that can be held by the player. However it does kind of break charge due to being able to hold so much meseta. I can release ASM patches that admins can use with their own EXE if they wish to implement it on thier own server but not sure if we would increase the cap on the player on Ephinea.
Meseta was a viable currency for trading in PSU. But in PSO with the existance of photon drops and such I think it would be hard to switch to meseta without unbalancing something. Meseta once you reach higher levels becomes pretty much useless. You only need a a few 10k to buy your fliuds/mates other than that use it for charge.
Bank is quite simple. You could actually already as an admin put more than 999,999 in the bank. Sega even gave something like 10m meseta in one of their later events. It's just a matter of raising the limit for when depositing. Which is 2 int changes in the EXE. Cap on the player requires more work (as its checked when buying, selling, depositing and also the sliders would need to increase to accomadate for the extra digits. This is hardcoded to 6. So I've had to replace the function so that it allows for more) but still relatively simple.
I like this idea if a full bank currently equates to roughly four PDs, then surely upping the cap might allow people to trade meseta for 10-20PD items.
If it can't be 'upped' enough to trade X amount of meseta for any item (or multiple items), then raising it to at least make it usable (in trade) for some higher value items would be a good, testing compromise.
Having meseta 'contribute' to trading value, even if it doesn't rise to become the 'currency' it should have been - would be cool.
Bad Idea, because of the future implementation of the Coren NPC that isnt implemented on Ephinea or Tethealla yet.
People will spam his 100,000 meseta item reward everyday and will have lots of chances to get his rare items everyday!.
It increases the posibility of people saving more than they are intended to, hence at the end there will be much more meseta in circulation.
Either way it's a custom feature that I dont agree that should be set for any server.