Does Al Oliver have a decent case for being in the Hall of Fame?

He's a 1st ballot Hall of Very Good player.

Hall of Famers don't need a case made for them. They made their case for themselves during their career and it should stand out enough to get them voted, without having to drum up hype for them.  So no.

He was one and done on the Writers Ballot. That's probably about right. Excellent outfielder in a time of superior outfielders.