The neck of a (bass) guitar has more effect on tone than the body so you can can put that on anything and it will still sound like a Modulus.
Swamp Ash, Alder, and Mahogany are the Big 3 when it comes to solidbody electrics. Describing "Tone" with words is always subjective but Warmoth does a pretty good job here...http://www.warmoth.com/Guitar/Bodies/Op ... tions.aspx
My recomendation would be Alder since it's less porous than the other two and easier to finish.
As for the top I like the ebony idea but I'd probably go with black dyed Flame Maple and then spray the back black with a very slight burstover on the front.