I’ll eat up anything they put out:
Perun (War economics, logistics, procurement, etc)
The Chieftain (Tank history and doctrine)
CGP Grey (Deep dives on random topics)
The Operations Room (High quality visualizations of historical battles)
The Intel Report (Followup topics related to Operations Room)
dnsl (Trolling in games)

Channels I’ll binge on once in a while:
Drachinifel (Naval history)
agadmator (Chess breakdowns)
Forgotten Weapons (Firearm history and mechanics)
Lockpicking Lawyer (Lock history and picking)
LifesAGlitchTV (StarCraft 2 commentary duo)
Spookston (War Thunder gameplay)
The Tank Museum (More tank history)
Real Engineering (Deep dives on interesting engineering)
Scott Manley (Space & rocketry related topics)