OK, how about this for variety in a three-knob format:
P goes to a push-pull volume pot that lets you switch between series and parallel wiring. On its own, a P in parallel is underwhelming, but it's good for blending with the bridge pickup (in either parallel or single coil mode).
Humbucker goes to a push-pull volume control, also switching between series and parallel. (Alternatively, if you're OK with some hum, you could switch between single coil and one of the humbucking modes.)
That gives you quite a few soloed and blended pickup options: solo P (series or parallel), solo H (series or parallel), blended P + H (series + series, series + parallel, parallel + series, parallel + parallel).
I would recommend using 500K linear taper pots for the volume controls: they'll offer fine control over blending (and remember that pickups blend best when the dominant pickup's volume is dialed back a bit). For the tone control, use a 250K audio taper pot.
That can either be a standard tone pot, or use a push-pull pot for two types of tone control: standard treble cut and a mid-scoop control using a
Wilde Q-filter (note the Bass version).
Here's how someone described the Q-filter in another thread: