Regarding rudders, skegs, and the like...
Given:

1)Retractable skegs are simpler in design and more reliable, but not quite as useful in seakeeping as a full-on rudder system.

2)A rudder is only effective to about 15 degrees of deflection or so, then it stalls and is simply a drag force on one side.

3)Variable-depth skegs are useful in creating a weather- or lee- cocking balance in certain conditions and so aid a making given point, but continual changes in conditions make this balance elusive in practice.

4)An expert should have the ability to control his well-designed boat without such aids, but should also have the good sense to use them when appropriate and available. Wasted energy on corrective strokes or constant leaning will in many conditions exceed the energy wasted in drag with a well-designed system.

So...

Let's put two "skegs" in the boat. Instead of aligning them to the keel, set them in a "V" form, each 10-15 degrees off the keel line. Either one deployed would act as a fully-effective rudder turned to that direction. A partial deploy would result in less drag and less turning effort, effectively the same as a partially-turned rudder. Each would be activated by connection to a footpeg, "toe-control" style preferred. The skeg boxes would be arranged with the open end of the "V" pointed forward, esentially following the lines of the boat. This would mean that a leaned turn would also have the appropriate skeg most in the water, and so would make the "skills" and the "tools" a natural fit.

It would be no particular matter to rig the gear such that only one would deploy at a time to avoid excess drag. On the other hand, an immediately available sea-brake by deploying both might have use in some conditions.

I'm just not sure if this compromise compounds the advantages or the disadvantages of the two systems.