The main kit i use is all Canon and is made up of :-
1dx mk2 body (work horse)
1dx body (backup)
600mm f4 L lens (the stag scope)
300mm f2.8 L lens
28-300mm f3.5-5.6 L IS (old but ok for a backup)
70-200mm f2.8 L IS mk2 (work horse)
24-70mm f2.8 L IS mk2
2x converter
The 1dx mk2 and 70-200mm are rarely parted unless i want a long lens for the stags.