What I did on one of my builds is sort of the Brent Mason Tele approach - to just use a 3-way strat/tele switch and then wire up the middle pickup through an additional 500k pot straight to the output of the switch. That way the amount of the middle pickup is dialed in and that works really well to get the most from the 3 pickups in parallel. I suppose you could add a switch to put the 2 tele pickups in series with that config as well.
Here's a snazzy schematic from Terry Downs that I used on mine:
Don't be confused by the series/parallel switch - you can leave that out with a standard strat pickup for the middle. Just add a series/parallel switch for the outside pickups.