I don't know about the very new machines but you shouldn't need any metric. I carry 3/8 thru 5/8 sockets and wrenches and a 6" extension and plug socket. Two torx bits. One is a T25 and I can't remember the other size but they fit both size torx screws on the machine. A changeable bit screwdriver with various size and types of bits. A small adjustable wrench and a set of vicegrips. That selection will fix just about anything on my 800.
I also carry a small length of mechanic wire rolled up, some zip ties, electrical tape and a spare plug. All this goes in a one gallon ziplock freezer bag in the rear box along with a small Slime air compressor kit with a small bottle of Slime, tire plugs and plug tool and a valve stem tool. I also can stuff a set of yuasa atv booster cables and a 15' tow strap in there. Oh yeah, I carry a spare belt too on really long trips. If you blow a belt in the boonies your machine is dead unless you can change it!
I haven't needed pulled out of the woods yet but may be jinxing myself by saying so.