I also have a D500 and own the Nikkor 10-24mm DX wide angle lens and have been extremely happy with it. I've also rented other Nikkor wide angles and prefer the one I purchased. Images are sharp, focus is pretty fast and it's not to heavy. Distortion in minimal and easily corrected in Adobe Lightroom.

I just received the Peak Design Sling bag late last week via their kick starter campaign. Inside I keep a Nikon D500 with a 10-24mm lens, a 18-300 superzoom, circular polarizing filter and UV filters for when needed, Manfrotto Pixie tripod, extra battery, a few small random things, a complete cleaning kit, extra QXD and SD cards and a quick reference card and my iPad mini. I also have a QXD card reader and USB cable tucked away nicely inside in addition to the lens hoods for both lenses. I could put an extra body or my 35mm and 18-80 mm lens in the space I have the pixie tripod as that space has extra room. The bag has straps on the bottom to attach a larger tripod, an expandable front pouch. I think the sleeve I keep the iPad mini in can hold a 13inch MacBook Pro?

The bags features are amazing. So much so that I'm going to sell my others bag. The bag is water resistant with water proof zippers. It also has anti-theft zipper-pulls and a place to attach a mount to clip your camera on via a Arca style plate. I've used it a few times wandering Chicago already and it's the most comfortable bag and doesn't scream, I'm a camera bag. It's a bit pricey so I'm glad I joined the kick starter campaign for the discount. This bag should fit your needs. Here's a link:

https://www.peakdesign.com/product/bags/everyday-sling