Swissempire
Poet Jester
The T/L/U/T system
I like the way you're thinking for economic system, and heres what i say would be good.
T=L/U/T
T=The total of your Economic Power, i.e Spending Points. Having this in front will streamline the system and help player WHILE keeping the level on complicatedness
L= Land Areas. Regions that you have that are rich in manufacturing or Agriculuture or something. Like Iggy's system. I already explained how this is more realistic. You could if you want to make it more compliacted, make some regions worth more than other, depending on richness. Infrastructure has a big role in this one.
U=Urban Economy. This is the sum total of your Urban power. It represents industry, city services, and other facets a city provides. Living Standards and Happiness and Confidence have a big effect on this, as it will go up or down with people's contentment and if people are rioting in the streets or live in cushy apartments. This encourages in warfare people to either try to capture a city or destroy it. Cities could be worth different amounts if you wanted that too. I.E. During WW2 Pittsburgh was worth much more to America than Los Angelos....
T=Trade Economy. Your Import/Export ratio and your trade with other nations or within your nation. This is impacted by your foreign relations and infrastructure. This way is someone embargo's you it isn't just an update event, it has dire economic consequences. This would also encourage the use of Tariffs and Free Trade. If nations choose to be mercantile and trade internation and intercolony, then it can show here too.
And thats the TLUT system.
Now, as for Economic Sacrificing and Growth, i say get rid of it. No sacrificing, but instead during wartime you can Mobilize your economy or get your a$$ into gear. This stops Siam from in 1 turn building and elitely training a huge army.
For economic growth, have factors that can be ENCOURAGED by the player grow or decrease it. They can fund government programs to grow the economic power in one area, but they can't put in 1 ecopoint to grow economy. Instead treat it like a research program, so intial investment and then keep working on it until it happens. Like a irrigation system someting like that. But when doing that take into account then infrastructure increases and Legislation and stuff like that to do it.
And lastly, whenever someone does something make them have a reason. No 1 point into growing infrastructure, make them describe what that one point is doing and WHY it deserves to grow the infrastructure, or WHAT is making the Living Standards higher.
Thats my thought.