To me, the whole concept of a "dream bass" is one that you could never imagine ever actually owning (short of some unexpected windfall, eg, lottery winning, discovering oil in your back yard, writing & recording a hit record that sits on the Billboard #1 slot for 27 straight years, etc.) I may have literally dreamt about some of the basses I currently own, but I don't call any of them my "dream bass"; likewise, I swear to god someday I'll own a Sadowsky NYC 5-string w/ swamp ash body, flamed maple drop-top, maple fb, & soap bars, so it's not really my "dream bass", it's just the one I'm GAS'ing for.
So my "dream bass" would be an Alembic Series II 4-string, 32" or 33" scale length, Large Standard body w/ Omega cut but also tummy- and elbow-bevels, red LED side markers, ebony fb & neck stringers, something exotic but subtle for a top& back wood (burled rosewood perhaps? or maybe AAAAA flamed and birds-eyed maple?), and -- here's where it really gets into Dream World -- modified Series II electronics that include selectable LP/BP/HP for both filters, a master Blend control to mix unfiltered signal around the filters (in parallel), and all pots & switches replaced by digital encoders so that their positions can be documented & recalled by an onboard microprocessor. iow, a bass w/ a pantload of knobs...that are instantly recallable, aka Presets.
And it has to weigh under 9lbs.
Yeah, that might happen...not. So I dream.