Well, I got through a graduate degree using WordPerfect on an A1000 before 2 MB of RAM were even available for it; you can't get much more classic than that! As far as capability, I still think WordPerfect can do more than 99.99% of users will ever need in a lifetime.
I used WordPerfect exclusively on my A2000 and was part of their Amiga beta team. As I recall, when AmigaDOS 2.0 was released WordPerfect had issues and never really got them fixed before they dropped support.
I used Scribble and Excellence for most of my Amiga writing work....
Bob