Hey BarnHouse,
You've got the right idea with your list of basic items...depending on the type of throwline pouch you have you can use that on your saddle for your ditty bag. Stuff several webbing slings in it at least, they are cheap and ridiculously versatile. They can be used as backup lanyards or stirrups for awkward reaches, they can be used to redirect your rope, or to fashion a false crotch, and they can be even used to tie off limbs or hang a pole saw. Then it would be good to have several extra triple locking carabiners because they can all be used in these situations.
The fact that I have now heard of several snaps opening and disengaging makes me reluctant to use or recommend them for lanyards anymore, you might as well just terminate in a triple locking biner.
I think it is a good idea as mentioned above that you have some type of blood stopper, even a bandana, just something, stuff it in your bag. I also think a cell phone is a must...
So, these few things, your saw + lanyard, your climbing setup, and you'll be in good shape! (PPE goes without saying...)