I've subscribed to around 200 channels, many are sister channels to a main channel, like Extra Credits and Extra History, Nightwish & Floor Jansen, Charismatic Voice/The Singing Hole, Tom Scott/Tom Scott plus, Hardware Unboxed/Monitors Unboxed et.c.
Some storm chasers like Pecos Hank, Reed Timmer & Melanie Metz, some science channels such as SciShow, Kyle Hill, Vsauce, ScienceAlert, Engineering Explained, BBC Earth Lab.
I've got a bunch of gaming channels, TotalBiscuit, Matt Barton, Spelrum, Jim Sterling, Liana K, Girlfriend Reviews, Noclip, Joseph Anderson, The Neon Arcade, AlexJordanVO, Luetin09 and Bricky, plus a few more. There's a couple of hardware channels like JayzTwoCents, Gamers Nexus, Linus Tech Tips and AdoredTV.
Some firearms, weapons and military related ones like Forgotten Weapons, InrangeTV, TFB TV, Garand Thumb, Demolition Ranch, Skallagrim, Shadiversity (MACHICOLATIONS!), Kentucky Ballistics, Brandon Herrera, Tacticool Girlfriend, Perun, The Chieftain.
And a few randoms like Ask a Mortician, Jonathan Pie, First we Feast, Steve1989MREinfo, Plainly Difficult, Bruva Alfabusa, Davie504, RoomieOfficial, ContraPoints, Viva la Dirt League, Juice Media, Tasting History, Nicole Johnsons Detour...
And a whole metric shedload of different artists, singers and musicians.
Oh, and DW News.