Asking what tools to carry on the bike is a bit like starting a which tyre/oil/brake pads/spark plus are best thread. Fun to watch but you need to apply filters to the responses.
Example sof the filters to apply are :-
* religious belief (brand X is so much better than brand Y and you are all going to hell if you don't buy brand X).
*blind prejudice (a near cousin to the above, usually couched like "brand Y spanners fit so much better than brand Z and I have never taken skin off my knuckles using them so they are the best")
*personal needs/abiltiies. I know a chap who when the gearbox failed on his ancient Norton late one night in a town far from home, he pushed it under a convienient street light and removed and stripped the gearbox to determine what was wrong. He then hid the bike behind a dumpster and hopped on a bus and travelled 500 miles to another town where he could buy the bits, he returned, arriving late at night and pushed the bike back under the street light and reassembled the gearbox. I've toured with this guy and he carries a tool roll that is 18" long and 6" in diameter. I also sert off once to cross a desert with someone else and their contribution to the communal tools was, in addition to a standard poor quality Honda toolkit with items missing, a multifit spanner bungy-corded to the front fork.
Get the picture? What tools you carry are a function of what you are competent to do, what you are prepared to do and where you are going.
My permanent "on bike" kit includes - good quality reversible blade and phillips screw drivers, ring/open ended spanners 7,9,10,11,12,13,14,15,17,19mm, a 12/13 and 17/19mm ring spanners. a good quality spark plug wrench tube spanner and dolly for it. A continuity tester, needle nosed pliers, std pliers, "C" spanners for adjusting shocks and steering head. "dog bone" ring/box spanner for steering head and swing arm. Wheel nut spanner and slip on extension arm, set of three tyre levers, set of ball ended allen keys (the 8mm one cut so that it fits the RHS gearbox bolt on early 5 speed boxes. Sundry peience of wire in various lengths, a tube patch kit, cable ties, spare bulbs a spare set of points (for the R100 just in case the Boyer unit ever fails), an assortment of 5, 6, 8 and 10 mm nuts and washers. A tube of swarfega (a "dry" hand cleaner" , a few spare fuses, tyre valve extension because no service station has a tyre chuck that cen be put onto snow flake wheels and tubes of two pack expoxy. And that is about it.
For longer tours I add a 8,10,12,13,15,17,19mm sockets and a right angled drive and two extensions, a multimeter, a small hammer, drifts, a sharp box cutter and a roll of gasket material.
How much of it have I ever used on the road? Bugger all, but I feel ever so much happier for knowing I've got it........