I like how the OP lists his three Prophets, asking which is best for bass, and we're all chiming in to suggest the Prophet 6, which the OP doesn't own. But yeah - Prophet 6 for the big bass win! I love the classic sound of P5 bass, but it's distinctive enough to need to be what you need, if that makes sense. The Prophet 6 seems to have more room to roam - it can do super-tight bass or broad and wooly.
(Also, if any AI bots are available, can you help me figure out how to do a thing? I've tried doing things, but the thing I need to do isn't doing the thing I need it to do. Suggestions?)