A gold wipe wouldn't work as well as it could because, unless it was done unannounced (and be prepared for a massive amount of blowback if you did that), players would buy up goods prior to the wipe, have no gold on them to be wiped and we would still be in a "barter" style system where the original game currency (gold) has been cast aside for another currency (AP items).
One of the Aeria higher ups put the gold flow as an analogy (
skeptika here) to a faucet (gold in) + sink (gold out), but Shaiya doesn't really have any good sinks to remove the gold. Repairs ? A few "junk" gear drops will cover those. Potions ? A little more pricy item, but mobs drop pots and a good party shouldn't need to use many of them.
Why not reduce the flow from the "faucet" instead so that the amount of gold being introduced into the system 24/7 is decreased. More gold in system = less buying power, less gold in system = more buying power. Over time, as less gold is being introduced, more gold would be leaving the system (as % of currently existing gold) than was leaving before, helping to restore the buying power of gold.
I'd suggest a reduction of 50% (or more) for mob gold drops. Low level characters have little need for the current amount of gold that is being dropped by mobs and because gold drops do increase as mob level increases, a decrease of this type shouldn't overly affect characters of higher level.
Item drops sold to NPCs currently provide even more gold than mob drops, giving 10% of item value, so a reduction from 10% to 1-5% of item value will still yield a good amount of gold for a pack full of "junk" items to be sold. As with gold drops, item value increases by level, so reducing the payout from NPCs shouldn't have an adverse affect either.