I have a few different bags, too. I started with a DSLR so I bought a Lowepro Fastpack 200 which was really nice. However the rangefinder is a bit 'loose' in there. For a while I used my Braun Paxette vintage 35mm film camera which is housed in a peli case all cut to fit the camera and lenses, very neat.
When I got my rangefinder I wanted to have a bag I could use every day for other things like my hard drive and keys, so I bought this little bag from Marks & Spencer (UK) and put the dividers from the Lowepro into it. I used a nice soft bag made for jewellery (I also love watches) in the bottom and it's nice and snug. It lets me grab the camera with one hand and have it in the right position instantly.
I would probably take my larger bags if I wanted to take both cameras with me but for every day the whole point of my new camera was for it to be something I will take everywhere by itself, so all I need room for is the camera, maybe a spare battery or two and a spare SD card, then whatever things I need. Keep it simple and keep it useful!
Not a PERFECT BAG by any means, but one I will definitely find comfortable and not be too precious of every day.
P.s It isn't waterproof of course, but I always carry a huge ziplock bag in the event of crap weather (I'm in the UK remember!!!) so I can stuf the whole bag and myself into it.
Cheers
ped