D&D character classes are dull.
Magic User. There is no way to take something that should be strange and wondrous and make it sound any more mundane. I hate "Fighter" as well. Nothing has ever sounded so boring, no wonder no one wants to play one. One thing I did like about 2e was the character kits. So you had your basic classes but how you played them made a difference. A fighter could be a knight or a barbarian or an archer or a gladiator or whatever really. This is good. None of these things need to be a new character class, another pet hate, but with a few skills and some flavour you have a character that has an identity.
Cleric grips my shit too but the reasons are different. It's a basic class but very prescriptive. I preferred the customisable priests, even if it was more work.
The only one that works for me is the Thief. He/she is a rogue, a tear away, someone with unusual skills. There's a bit of flavour there before you even begin. That's good too.
You can start banging on about Paladins and Rangers and Druids but let's not, they already have a great deal of fluff built into them as character classes. Plus they're generally the only reason anyone plays a human. Getting off topic.
So what makes Joe the Fighter different from Fred the Fighter?
Well Joe is a Rekkar tribal warrior, a carl sworn to the Jarl of his people. So I'm renaming him using my random Rekkari name generator, a handful of dice tell me he's called Rendred. A roll on my Rekkari tribal generator tells me he's from the Snow Spear tribe.
Fred I've decided is an ex pit fighter who fought his way to freedom in the Battle Pits of Nox Aeterna. Sent there for a crime he didn't commit (obviously) he took on beasts and men in blood drenched combat for the amusement of patricians and commoners alike, until skill and chance granted him freedom. Still branded and tattooed as a slave, he is now free to pursue his fortune and probably the conspirators that sent him to the battle pits in the first place.
I terms of game mechanics though, what are the differences between these two characters? Well Rendred is a weapons specialist in the battle axe, plus he will have wilderness related skills like tracking and survival. Fred will get half penalties for fighting with dual weapons due to his flashy entertainment based fighting style. Both will experience social stigma in the city as a barbarian or freed slave.
There we go. Two fighters, hopefully very different. Rekkar warrior and Pit Fighter is what I'd be writing on their character sheets.
Now, about those clerics...