Hey there. Before I answer the question, I just wanted to let you know that (I don't know if it was intentional or an accident, but) double posting is against the rules. Just a warning though, and I deleted the extra post.

And now to your question. I think I'm going to assume that you're referring to canon Hogwarts professors, and not SS ones. But anyway, I think it's a tie between Professor McGonagall and Professor Lupin. We didn't really get to see a lot of the former's lessons, but I think they'd be awfully interesting even if she herself seems strict, and of all the DADA professors (Moody notwithstanding as he wasn't actually Moody when he taught), I think Lupin was the one who really tried to teach the students the practical applications, and we know he understood the reason why the subject is an important one.