For the past few years I've been almost fetishistic about keeping my photo kit lean. After decades of lusting after big, hugely featured (and very heavy) cameras and lenses, I'm now equally fanatical in the opposite direction. As they say, the best camera is the one that you have with you, and that old saw is about as true a thing as has ever been said. Who cares about the awesome Hasselblad that sits languishing on the metroshelving back in the studio because (a) it's too goddamned heavy to schlep around and (b) every single exposure ends up costing more than a buck, because it's film?
The champion when it comes to size is obviously the phone, in my case currently an iPhone 7+. Totally awesome camera, in my pocket all the time, and certainly my go-to. But there are other circumstances that call for greater firepower, and this is the dangerous territory where gearheads end up carrying "thousands of pounds of the latest ultra lightweight equipment" (as my mother puts it when she sees me and my brother heading off for camping trips with backpacks that threaten to tear our knee cartilages before we even start walking).
For me, the limiting factor has become my camera bag. Not any camera bag, but my small black canvas Domke. They're a venerable brand, with a huge stable of serious camera bags for serious photographers. Mine is the smallest bag they make (okay, they make smaller ones, but those are called 'pouches' and are not technically 'bags'). It has one compartment, with a little padded slot for accessories. Two small external pockets, a velcro flap, and a shoulder strap. It also has a big loop through with you can thread a belt, to make it a fanny pack. My bag is faded, frayed, battered and...perfect. I can fit two small camera bodies, and three really great lenses. Memory cards and lots of batteries. An enema bulb—to clean the sensor. Lens cloths. A small tabletop tripod. And I've even fit my iPad in there. It's just amazing what you can fit in a tiny bag!
Allowing my bag to be my constraint has informed my choice of camera, too. The days of the honking Nikons are over. Now I use the small Sony's, not even the full-framers, but the smaller APS-C jobs, the NEX-7 and the A6300. I often wonder (agonize!) over whether I should upgrade to full-frame, especially given the limitations in printing large. But I recently printed a bunch of images at 17' X 22" with my friend Tim who's an amazing printer, and they looked great! So small and lean is the name of the game, and shall remain so... Until I find a reason to rationalize otherwise!