For anyone who has actually done the math, you know that the most resource-efficient and time-effective way to increase your production of any given resource is to do the following:
1. Improve your core resource provinces first. At 100% morale, core resource provinces produce resources at FOUR TIMES (4x) the rate of captured resource provinces. If the only goal is to increase resource production, improving your core provinces first is a no-brainer.
2. If you are so fortunate as to have a "double resource" province, improve it before you improve your single resource provinces. Double resource provinces are those that produce resources at twice the rate of an ordinary resource province, there are a limited number of them on any given map, and not every country has one.
3. If your only goal is to increase resource production, build all three levels of infrastructure in a given resource province before you begin to construct a level 1 industrial complex there. Both an L3 infrastructure and an L5 industrial complex increase resource production by 50% in a given province, but the L3 infrastructure takes less time and less resources to build than the L5 industrial complex.
4. For speed of unit production, it is usually smarter to build out your existing four or five industrial complexes before you add new ICs. This is a separate issue from resource production.
5. Naval bases should only be added to coastal ICs as needed for the production of naval units. If your goal is to increase resource production in a given coastal province, then a naval base should only be added after L3 infrastructure and an L5 industrial complex are completed. Naval bases are the least efficient way to increase resource production, i.e., they generate the least return on your investment of resources to build them.
6. Adding naval bases to non-core single resource provinces rarely makes sense if the goal is solely to increase resource production. For example, adding an L1 naval base to a non-core oil province consumes 50 tons of oil per day when the base is enabled/active; at 100% morale, an L1 naval base in non-core oil province will increase oil production by about 40 tons. Thus, it's a net loss to total production.
7. Adding fortifications to non-core provinces to increase provincial morale, and thus increase resource production in a non-core resource province is the least efficient and most expensive way to increase production of a given resource, and it should be undertaken only after your core provinces that produce the same resource are fully improved. And, yes, I recognize that the construction of fortifications is often undertaken for reasons other than resource production, i.e., morale stabilization in a captured province, or for actual defensive purposes.