Remus John Lupin (of course)

Definitely Lupin

I think Tom would have been amazing

Remus Lupin was the best at teaching, as well as just caring for his students. Barty Crouch Jr. as Mad-Eye Moody is a second since he mostly taught them very well, but he lacks the sympathy and understanding Lupin has.

Remus Lupine!Definitely Lupin

He is the best DADA teacher

Dumbledore. I mean sure it's fantastic beasts but Dumbledore is just so damn cool.

Remus Lupin-

Lupin

Remus Lupin