I kept a ToPeak multi with one bike.
Usually the 'kitchen sink' pencil case accompanied every trip.
It had:
Chain tool
Leatherman
5" Vise Grips
Spokey
4, 5 & 6mm allen keys
8 10 mm spanners (and often a 6/7mm double-ended one too)
Tools are like rainwear; you hope you never need them but they make life more comfortable if the worst happens. There's also the belief you may help someone else.
I've never in my life broken a chain! I understand it does happen sometimes to fixie riders, but unless you're doing a tour of chain-wearing length, I can't see the need.
Spokey - you mean one of those lightweight plastic ones? I have one but never use it - wrong gauge, left over from some past bike. Should get another.
Spanners - this demonstrates my dislike of multitools. I've dug out the one I have - can't remember where it comes from. It has allen keys 2, 3, 4, 5, 6, 8mm (I'm guessing, they're not marked). I can't think of a use for the 2 or 3 but the 4 and 5 could be useful, potentially the 8 in case of loose crank I suppose. Not exactly likely, but potentiall v serious!
Then it has 9, 10, 12, 13, 15mm ring spanners. There's not a thing on my bike those will fit!
An 8mm socket. Hmm, not sure about that.
Straight and cross screwdrivers. Could be useful.
But... I could just take the screwdrivers and relevant allen keys for a saving in weight and gain in useability. Of course I don't though. Except in fact I do have 4 and 5mm allen keys in tool kit, again they're left over just-in-case-it-isn't-tight from fettling brake blocks and something (I think the 4mm was from cleats).
I used to have a packet of citric acid crystals -baking type - when MiL showed me how they can clean your hands w/o water! Probably not as effective as baby wipes though.