I'm thinking that it would be good to install an automotive style plug to front panel so I can use a variety of electronics.
How does this front panel socket system seem?
Suzuki VStrom Electrics
This is a good system BUT if you are thinking of using it for heated riderwear you cannot use an auto cigar type outlet for this purpose - not rated for high wattage. Instead you must use a Powerlet (BMW/Euro) type socket (higher amps/watts rated). You will then need an adapter to go from BMW socket (male) to COAX type connector (female) to connect a heated vest or liner.
I have one of each type of power outlet on my bike - one for heated clothing and the other for recharging or running low-draw electronics. I also have them on a Rick's Auxiliary Shelf.
If you are planning on having several other powered items installed on your bike you should consider, as Frostypuck
suggests, a power block such as the PC-8 that EB sells. I have that too and I only have one open circuit left!
A GPS unit draws very low power so you don't have to use anything heavier than 20 gauge multi-filament wire but for the BMW (Euro) circuit you should use at least 16 gauge wire - I used 14 gauge on my bike - the difference in weight is negligible. If you decide to rig it so that it runs only on a "switched" circuit you should use an Eastern Beaver solution, whether that involves its own relay system or through the PC-8 block.
Installing new electrical circuits in the Wee/Vee (or any bike) is best done with the seat, tank and side fairings removed. Have fun - I personally enjoy doing this kind of work. With experience (your car, boat, trailer, etc.) you get better at it. But, if you are not confident in your abilities, be sure to seek the advice and help of someone who has the knowledge, skill and experience. It will save you grief down the road. Also, be sure to use all-weather connectors up front where the wiring is exposed to rain and splash water.
Have fun with your project.