Suitable cabinet to match with a Line6 Helix?

I'm trying to downsize into a single rig that is suitable for multiple instruments. Bass, guitar, keys and V-drums. I'm retired and most likely will not be gigging. Bass is my most worrisome because I want the bottom to sound good, and to be able to use a 5 string. For bass I will be using a Line6 Helix and Boss ME-50B along with some pedals. I know some guitarists and keyboardists who love the Line6 StageSource L2m but those are expensive, and I don't know that a 10" two way cabinet will do justice to a 5 string bass. I think that I would prefer something like the Electro-Voice ZLX-12BT. That would be on budget and not too boomy for keys or guitar, but will it handle 5 string bass okay? Do I need to move up to a 15" cabinet or add a sub-woofer? Would a pair of the 12" two way cabinets sound better than a single and do away with the need to move up in speaker size? Good sound is more important than volume.