I use very simple handlebar mounted rocker switches color coded for use.. MrGizmo bike has 4, two per side. However there is a whole world of combination deluxe handlebar switch clusters that may solve your goals. Things like a pair of these, but better.
5V/4.2A Dual USB Charger Socket Waterproof Motorcycle Handlebar Clamp voltmeter Thermometer with on/off switch for Phones/Tablets/GPS
Some do quite a multitude of tasks, might even be one that holds your toothbrush. Peruse the listings on e-bay or Amazon and you might find a combination cluster, or series of swiches
Otherwise the custom under-binnacle box sounds great.