Bikepacking - a viable alternative to racks & panniers

... work best carrying certain things in specific places...for example, you can't just throw a couple of things in the saddlebag or it will flop about...they're designed to fit a certain minimum amount in them in order to function properly.

I totally get that. Had a look at their standard items that might be enough for the kind of use I want. I just can't be asked with the Carradice QR bracket and the bags. I want something I can just strap to the seatpost and go for day to day use. Then use the same saddlebag for light tours coupled with a handlebar bag, or something similar to Salsa's front rack.

Is there anything similar to Revelate's Viscacha design?