Am I the only one in this thread who thinks that gold as a separate XP track is a good thing and players shouldn't be penalized for accumulating and spending it? Leveling up in most classes means a couple choices a level, sometimes pretty obvious choices too. Choosing whether to upgrade your cloak or your weapon or get some fancy wondrous item is way more interesting than leveling. The unchained rules for scaling bonuses are even better because they free up the big 6 slots for interesting choices. (I've been using limited custom crafting for a similar effect.)
The economy, weights and conversion of coinage and prices of items are terribly unrealistic, but they were only ever meant to restrict player access to items of excessive power.
Baseline the game allows players to convert their wealth into lightweight trade goods of enormous cost (an example is wish diamonds) and back again with no loss. We've always played it that as long as you have a few pounds of encumbrance or extra-dimensional space you're covered for carrying your savings because bookkeeping that gets tedious fast. Hauling out a dragons horde can be interesting though.