After many years of wrenching on bikes and thousands of miles riding, this is the mini-toolkit I have come up with for randonneuring and for Paris Brest Paris. 568 grams total, about 1lb and 6oz, not too bad.
(2) cables- one shifter and one brake- 38g
tire lever- 13g
Allen hex wrench set- 75g
spoke wrench- 17g
multitool set(chain tool, 8/9/10 wrenches, little pliers)- 161g
bag of various nuts/bolts/zipties/chain master link, spare taillight batteries- 58g
Y socket wrench (8mm/9mm/10mm)
*crank tools(ta extractor and campy crank bolt tool)-143g
*Normally I don't carry the Campagnolo crank bolt wrench and TA crank arm extractor, but I do have to take off a crank to fit my Hanford in the S&S suitcase for travel, so I thought it would be best to bring the crank bolt wrench, and while I'm bringing that, I might as well bring the TA extractor, as anything is possible and it is a unique tool.