Indeed, Tony Dow ended up becoming so popular, that in the later seasons, the writers started writing episodes in which Wally would get into the schemes and scrapes that Beaver would usually get into, with Beaver becoming more of an observational character.
And, of course, Eddie Haskell.
Not to mention Clarence "Lumpy" Rutherford, bad girl Judy Hensler and even Gilbert Bates.
Hilarious in Hindsight: In one episode everyone was aghast that Beaver was actually selling water to people! Mind you, it wasn't so much that he took advantage of inside knowledge that the water main would be shut off or that he was selling it out of a bucket on his wagon, but merely the fact that one person could be low enough to sell water to another person! How Evian spelled backwards of them!