The acoustic/electric is a bastard instrument that doesn't sound good un-amplified, and is clumsy to play either way.

Buy an electric bass, or bite the bullet and try an upright bass.

I play both--my electric is a fender style fretless that is a dream to play, and the sound is great. The acoustic/electric hybrid guitar gains no advantage from being "acoustic"; The body is too small to make good sounds in its lower range.