You can get a multi tool with a chain tool on it. Extra weight would be minimal. A chain tool is good in the event that your chain breaks. It's rare, but could happen.



You can also get some glueless patches that are maybe the size of a postage stamp and weigh next to nothing. I'm like you- I prefer to just change the tube on the road and worry about patching at home. The patches are good to have just in case, though.