I've noticed several times throughout the day, on any given day, that items are sold out. With so few people playing, would the market benefit from a shorter time to market?

It is currently 4 to 6 hours.

Yes...

That value is in keeping with the other servers based on time per turn. Given there are SO's and the volume hopefully matches between play types (farmers, techers, etc) or alternatively, balances out with market forces (e.g. people creating their own oil/food/tech start), shouldn't the pace be the same?

Or in other words, I think it should average out over time, what's the benefit to having a shorter time to market (other than to help individual suppliers keep a consistent price, so one doesn't get priced out and have to wait or recall)?