As a grognard, I understand the purpose of the electrum piece pre-3E. For those of you unaware, it used to be 1000 cp = 100 sp = 10 ep = 1 pp, with 2 ep = 1 gp as today, which (supposedly) was an approximate medieval exchange rate. Gp was still the standard, but you often carried small coins since you never got change and there was typically a charge for currency exchange. However, for reasons unknown, D&D got rid of the ep in 3E when they moved to a metric exchange rate. When reintroduced in 5E as a half-coin, it no longer really seems to fit anymore. I'm considering the following houserule for my next campaign, and I'm curious about how the players on the board would feel about it if suggested for your game.
Rather than having ep be equal to half a gp and 5 sp, I'd simply slide it in as 100 sp = 10 ep = 1 gp. From a mechanics perspective, everything in the PHB that costs "gp" would instead be paid as ep. This would provide an additional coin so that characters can carry around more weath more easily. While many groups have "infinity pockets" that hold coins, I try to hold to both encumbrance and container capacity (a pouch can only hold 600 coins, for example). Having a higher coin rate would make it easier for the players to carry their wealth without having to buy gems/jewelry/art or take up space in a bag of holding.
Edit: since it's been asked a couple of times, copper and platinum would still exist in their normal positions, relative to silver and gold respectively.