Each character's best season
Cory: Season 5
Eric: Season 4
Topanga: Season 5
Shawn: Tie between Seasons 5 and 6
Alan: Season 4
Amy: Season 4
Feeny: Season 1
Turner: Season 2
Angela: Season 6
Jack: Season 6
Rachel: Season 7
Cory: Season 1
Eric: Season 2, 3, or 4
Topanga: Season 1
Shawn: n/a
Alan: Season 4
Amy: Season 4
Feeny: n/a
Turner: Season 2
Angela: Season 5
Jack: Season 6
Rachel: Season 6
Mr. Feeny was the most consistent all throughout for me, so I couldn't really pick one season. Though, I can see why you'd choose season 1, because he was just the teacher next door, and not the Grandpa he was to everyone for almost the rest of the show.
Cory: Season 2
Eric: Season 4-7
Topanga: Season 4
Shawn: Season 4
Alan: Season 1
Amy: Season 1
Feeny: Season 5
Turner: Season 2
Angela: Season 5
Jack: Season 6
Rachel: Season 6