If you could add any Body/Neck Option(s) to Warmoth's selection..

[Loomi]

A pointy 6-in-line headstock that fits in a normal neck blank.

 

[tubby.twins]

Singlecut Gecko bass bodies.

Imagine this:

plus this:

resulting in this:

(Please excuse the crude mashup - my GIMP skills are a bit rusty.)

 

[swarfrat]

The guitar version of the geck double cut is called "Seven String Model".  But picture this: guitar version of jazz bass, maybe with the jazzmaster lower stub horn. Call it the Basscaster! (Intentionally mispronunced pun, as in largemouth)