I carry a Leatherman Wave in my backpack with survival gear. Other than that I added a 1/4 drive ratchet, extension, socket (s), second 9/16 wrench, spare bolt and washer to hold the secondary on, and a few individual allen keys. All fit inside the factory tool kit. The things I added over the factory stuff, for about any of my sleds, are for changing/adjusting clutch weights, belt deflection/removal, and for adjusting/changing my belt drive belt. One of the allen keys is for the bolts on my handlebar riser and the other is for my team tied secondary deflection bolts.
Also have a small roll of electrical tape, spare fuses, small Loctite tube, and zip ties in a small container in my tunnel bag I forgot about.