Guitar looks great, but I reckon you should change those switches. I could see those momentary on 'preview' positions driving you nuts over time.
If you want simple, just an off/on switch wired as described above will do it.
If however, you can get proper on-off-on switches (that stay where you put them!), then you have a nice option of, for each pickup: normal phase, off, reverse phase. This would give you lots more sound options in combination, as well as let you optimise the hum cancellation between pickups. Im sure theres a diagram on Seyour Duncan, but I'll post one if you need it.
Example:, if your middle pup is reverse wound as on a normal Strat, then neck/middle and middle/bridge combos are in phase and hum cancelling. Neck/bridge however is hum cancelling if revese phased, giving you a very different sound with low hum.
Mini toggles usually all fit in the same 1/4" hole, so no change to your bodywork if you change the switches.