Retrospective or Peak Design Sling?

I don't know those brands, but I'm very happy with my Think Tank Turnstyle 20 (the biggest one), which can carry two bodies with lenses, plus another 4-5 lenses (the Nocticron is my biggest lens).  I use this for general purposes, and for my under-seat carry-on of all my photo gear when traveling by air.  I also have the Turnstyle 5 (the smallest one).  Both very well constructed, comfortable.

I cannot comment on either of these bags; however, I think that I have solved my own bag problem, at least for the time being. I have an Ugg messenger-style leather bag that I was using as a camera bag. The dimensions are 10" W x 9" H x 4" D. I bought a Tenba BYOB 9 inset bag, which fits quite snugly inside the Ugg bag. The Tenba inset has 3 compartments which holds: 1 Panny GX-7 body (center compartment), LUMIX 35-100 lens (left compartment), LUMIX 7-14 lens (right compartment) and a LUMIX 14-45 lens (on top of the 7-14 lens). Things are a bit tight, but I can manage to change lenses without too much trouble. The nice feature is that this setup does not look like a camera bag. Perhaps you have a bag that you like for the office or computers, etc. that you can convert.

I like the look of the one you have in your closet.

F.

No wasted space in this sling bag. On the right is the 40/150 f2.8. Left top is 7/14 f2.8. Underneath on left is the 60 f2.8 macro laying on its side (given its thin diameter, makes much more sense positioned this way than standing up). There's a collapsed 12" reflector in a pouch along the left side of the left compartment. M1 Mark 2 camera holds the 12/40 f2.8, plus blower bulb for potential lens or sensor dust situations.

Not sure if this has been mentioned, but the dividers can be positioned to accommodate whatever width you want. You can also add more dividers, but don't see how that would be helpful given the size of the bag.