A few comments elaborating on some of your points (and you probably know this stuff anyways):
1) It may be helpful in a future post to elaborate more on the distinctions between types of load (base, intermediate, and peak) and how the characteristics of each form of generation play into that, because this does influence capacity factor (as you put it, the typical order of dispatch is nuclear first, then coal, and then gas). Because coal and nukes utilize steam turbines, it is more practical and economical to simply run them flat out, which makes them most suitable for base load. Gas combined-cycle plants have a gas turbine in the mix which makes them more flexible and thus more suitable for intermediate load (or load following) which has the effect of reducing the capacity factor.
2) Some people may not be clear on how nuclear has the lowest running costs. Costs for power plants are broken down into capital, fixed, and variable (or fuel) costs, and it is important when formulating policy to have a firm grasp of the tradeoffs with each fuel source. Everybody knows that nuclear has massive capital costs, but less understood are the low variable costs, and this is the only thing that keeps nuclear in the game. The only way to recoup the costs are to take full advantage of this and extract every last bit of energy from the fuel. By contrast, natural gas has a clear advantage over coal and nuclear in its (relatively) lower capital costs, but not when it comes to fuel (although as you mention, the shale gas revolution has cut into coal's normal base load advantage).
3) Because of the variability of the "fuel", wind and solar are classified as energy resources as opposed to capacity resources, and this factors into why they must be curtailed. To put it another way, conventional generation is dispatchable; the fuel can be throttled back and forth as necessary depending on the load curve, whereas wind and solar cannot (though the efforts to make them more grid-friendly should not be overlooked). For this reason, wind and solar have sometimes been characterized as negative load.