Another way of looking at this is.....

Get to know your Bike Well.

If your going touring and intend doing 4 to 5 thousand miles on the trip dont set off on a worn out chain and sprockets , or 2 mm on your brake pads .

If you prep your bike before the trip you should not need to carry much at all.

Consider fitting new C and S and Pads before you leave, also start the trip on new tyres. { my C and S on my Tenere have now covered 12.000 miles and are still OK} I did change half worn pads which I kept to refit at a later date at 7000 miles because we had a 4000 mile touring holiday to do.
If your bike as already done more then 15,ooo miles consider fitting new wheel bearings and strip the rear linkage and head stock and repack with high melting point grease.

The only problem XT's seem to have is the R/R which now we know about this can be fixed by a small Mod to the top of the plug.

I have only ever snapped one chain in 35 years so as long as your chain is adjusted correctly and looked after they should be no problem.

A extra clutch cable along side the one in use is a good idea.

So I only carry what cant be bought from a DIY store

My spares Kit...........

Brake and clutch lever
front and read tube
12 volt pump
puncture repair kit
clutch cable
tow strap
AA card.

I would also carry front and read wheel bearings, if I were going through Africa/ south america / Far eastern Russia.