You could pass on the switch and install another volume for the secound coil. I don't like toI always have to take their word for it when it comes to the finer details of electronics. I liked what I heard. I didn't really need series/parallel. I have that on my Rami 6 with the dual coils.
Side note: the Stambaugh semi-hollow guitar I have on order will have a 5 way for each pickup to allow for each coil, series, series out of phase, and parallel. I suppose I could theoretically add a cocked wah capacitor on one of the single coil settings to add some difference.
Deal with single coil "issues" so for me it is humbucking all the time. Went with the Aundre preamp as it has a preamp for each pickup and have seen issues with mismatched pickups. Also prefer 2 band EQ.