Which of the options for the various classes do you consider the more powerful? Here are my initial thoughts, which are admittedly not based on playtesting. Where I haven't yet developed a strong opinion yet, I will leave the class out.
Bard- College of Valor. This is the 5e Factotum.
Cleric- Tempest Domain. Heavy armor, martial weapons, and a powerful domain spell list. This is not your father's healbot.
Druid- Circle of the Moon. For me, druid is wild shape shenanigans.
Monk- Way of the four elements. This is basically psionics.
Paladin- Oath of vengeance. Not gonna lie, I choose this one because it is the option that is least likely to make the party hate you.
Ranger- Bard, College of Valor. It is a better ranger than the ranger.
Rogue- Assassin. Have you read it? It is straight murder.
Sorcerer- As much as I love the wild magic table, Draconic Bloodline is more powerful.
Wizard- Still probably either Conjuration or Transmutation.
What do you think? I'm happy to edit this post over time in to a bit of a guide.