another question about order

Well, I'd put the compressor first, overdrive/distortion second, and then the other stuff after it. The RBI is a preamp, and I am unclear on what he peavy Kosmos does, exactly. Could you elaborate on what it does?
EDIT: okay, so it's a kind of filter device. I'd put it after your other effects but before the RBI, and then run all that into your amp heads and cabs.

 

Bass first, amp last, pedals in between Seriously I'm not trying to be difficult - the correct answer is whatever order sounds best. Google "Bass Player Pedalboard primer" and check out Bryan Beller's article on ordering of pedals. Note even that order is a recommendation - ultimately your ears are the best judge. I followed it but found by listening the only change I preferred was having my fuzz before my drive (I would have expected drive into fuzz).

Here it is: http://www.bassplayer.com/effects/1167/pedalboard-primer/26257

It can depend on so many things, like how much of each effect is dialed in, which ones you like to turn on at the same time, what sound you're going for, etc.

 

This guy explains it better than I did.

 

Nothing but speaker cable between amps and cabs.