In that picture, using 250k audio (the ones from Warmoth are good) and 250k/500k linear pots will get you pretty well dialed in for most humbuckers. I prefer the 500k for humbucker volume, but the 250k is ok for the tone controls (unless you're a real treble nut, but then you'd not be using humbuckers probably...)
The caps... standard for humbuckers treble control seems to be about .022. Some folks like a smaller .015, or will hand pick from a selection and get .018 or .020 or whatever. You're call. On the middle control - you can use the capacitor to dial in more or less "lows" retained when you cut the middle. A good starting point is .022, but... you can go smaller (more lows retained) or higher (fewer lows retained). Eliminating the capacitor all together will result in a very thin, nearly single coil sounding tone. If you do that, its suggested you but a resistor in place of the cap, because if you turn the pot all the way the effect is too great. A good resistor to try there is from 15k to 47k, depending on the pickup and the inductor.
The inductor is a humbucking Lawrence Q-filter, which, in its latest incarnation runs about 1.8hy and 55ohms impedance. Yes 55 ohms. Very very low, which is why you need that blocking resistor if you dont use the cap. If you want some fun, you can put two Q's in series and retain more highs when you cut the mids out. Or you can put two in parallel and retain less highs. The impedance is so low, that going to the 27 ohm or 110ohm combined impedance creates no problems. If you use two in series, you get 3.6hy and what that does is bring the retained highs into the fundamental frequency range of the high E string, and 2nd harmonic range on the B and G. Personally... I find the 1.8hy just about right, as it retains the very top end of the high E fundamental and 2nd and greater harmonics of the other strings. In other words, it cuts the middle, and retains the "crisp" to a great extent (until turned way way down). I use a .022 cap, but... if you wanted to thin it out a bit you can use a larger cap (lets more thru to the inductor). Those Q filters are small cubes about 3/4x3/4x5/8 tall. Easy to fit. I mounted it with a double sticky foam tape square. They run $20 from Lawrence (give them 3-4 weeks to get it to ya tho, they're SWAMPED)