Thank you both for resurrecting this thread, as a relative newcomer to BCG I was unaware of this treasure trove of information! I do agree this needs to be a sticky or even a new forum subject to contribute to.
Hard to think of any gear hacks besides what has already been mentioned here. I would say this, more and more body plate companies (RRS, Smallrig, Leofoto, et al) are using magnets in their base plates to hold hex wrenches, this hex wrench is the typical size for other lens plates etc. so instead of rummaging through your bag, you can usually grab the hex under your body for numerous applications.
Now that I'm getting into longer/bigger lenses, I've come to appreciate my Black Rapid strap even more and also appreciate QD connections on body/lens plates. Connecting my BRS to my Kirk QD Lens plate/foot makes carrying this bigger/heavier lenses without putting much stress on the body itself.
Right now a challenge I have is figuring out what is the most convenient way to carry TC's. I want them to be quickly accessible and not have to dig through a pack to grab one and put one on and then store the caps quickly. Maybe a smallish Thinktank Photo lens changer attached to my belt would be helpful, but curious what other solutions y'all have come up with for convenience. I also wonder if there's anything I might be able to attach to my Black Rapid strap as it is almost always with me with a big lens kit...
Another great accessory for the bag I don't believe I saw mentioned is a nice set of running gloves, newer ones have silicone fingers and palms for better grip and while others have mentioned rubber bands and even rubber dish gloves for helping to remove stuck filters, the running gloves can also serve this role but help when temperatures dropped unexpectedly (or expectedly and you just forgot to bring gloves) and don't take up too much room in the bag. Costco often carries the Head brand for a decent price.
Another tip would be some small carabiner clips, either D ring style or S style, along with some paracord and a small arc lighter - I'm always wanting to attach something to something and this is a great way to do so.
