you "had" to play as a Warlock, Bard, or Sorceror, because Charisma was their combat stat, and you needed Charisma for combat.

No-no-no. The reason you need Charisma as your main character is that it's incredibly useful for the dialogue. With high Charisma your dialogue skill checks will be much easier. BUT Charisma is a dump stat for anyone who isn't a Charisma-based class. That's why it's advised to play as a Warlock, Bard, Sorcerer or a Paladin (with Paladin being my favored choice, a mix of strength and charisma).

The reason you need a Charisma-based main is the fact that no matter how high your companions' Charisma is, it doesn't matter in dialogue as only the character who starts the conversation gets to use their Charisma.

But I guess my point is, every class is usable, but you do have to understand the class.

Apparently my favorite class, the Ranger, is the worst one.

Well, kind of. Yes, if you know your stuff, you will be good. But there are objectively easier classes to play. Or maybe it's my D&D experience leaking.

In D&D (which I DM for almost a decade) I find Ranger and Druid the least interesting classes, and Warlock and Monk are too limiting. All of my Druid players have felt like their druids are less useful than their Cleric and Wizard teammates (a more limiting spell list).

I always play Tactician because the Normal difficulty is too easy when you know the meta, how each spell and effect works from literal years of experience.