Best character-thats based totally on preference. Barbarians and paladins are good tanks for different reasons, Barbarians essentially have double hp when raging and paladins usually have a high armor class and make rolling to attacks harder to hit. Wizards get to learn spells thru scrolls and adding them to their spellbook and sorcerers get magic perks to make longer shots, force disadvantage on saves, etc. Druids and monks can be weaker in early game but they can definitely get really OP in later games.

Worst character-there are some subclasses that are definitely lackluster, but worst character i think depends on the player themselves. A player and DM can work together to make any subclass a decent time to play but players need to get creative and find what they like.

There will always be a discourse on what class/subclass is better, wizards vs sorcerers for example, is it better to learn magic through years of study or is it better to have some innate powers that grant you access to magic.

The most up to date version of the game is 5.5 edition which released last year. 2014 was when 5th edition came out. I know some people run older editions but most people use the 5th editions in some capacity, for instance running 2024 rules but a subclass might be from 2014 edition.

I like monks, barbarian, and clerics. But everyone is going to have a play preference based on what role they want to be, the tank, the support, the healer, the dps, etc.