While that's a sophisticated way to handle it, Locklear and therother, I think that what we're seeing is that CA slapped a very simple change on RTW (vs MTW) to stop people from running out unexpectedly. This is a game with a thousand things for the CA crew to work on - they can't do everything great. So they did something very simple which addressed the short-term problem, but created long-term problems of its own. In this light, the idea of having two statistics for population seems beyond the level of sophistication that CA has been willing to spend on this particular area (out of the thousand that they're trying to address).

I propose instead a somewhat simpler solution - to let folks queue all they want, but not have it affect the pocketbook or population until the turn it "hits" - but, have a simple warning system when hitting the End Turn button that says whether too many denarii or population have been used that turn. In the case of population it's easy to point to the city in question; in the case of money, one can't point to any one place - but one can point out that it's overextended.

And of course if they have the routine set up to test whether you're over the denarii limit, they could easily implement something that says whether you're over at any given moment. Which would mean, you could play with your queues and watch some little meter (instead of having to End Turn and cross your fingers, a bunch of times in a row).

Just some thoughts. In truth we don't know all the complexities CA is up against or has thought through, including how much time the CA crew has to spend on the many challenges of such a multi-faceted game.