D&D 5E DEX-based spear wielding Fighter

[Cap'n Kobold]

You need to look at some longsword fencing... definitely not just raw strength.

No, but there is a fair amount of athleticism involved: moving, jumping, rapid weapon movement. That is raw strength in 5e.
Once you remove skill out of the equation in proficiency, splitting offence into Str-based and defence into Dex-based is a reasonable compromise rather than using an average of the two for each.

Very agile, though. Some of his kills look like SA would model them neatly.

Probably just crits. He is a high-level Champion fighting much lower level opponents mot of the time.

Realistically, multiple 'stats' would go into most checks. DEX & STR both matter to attacking with a melee weapons. So does being alert for openings & able to 'read' your opponent (WIS). So does aggression/dominance, or, conversely, feinting/deceptions (CHA). So does Endurance (CON). I'm sure we could work INT in there, too, RQII did, along with reach (SIZ) and connectedness to the universe (POW).

D&D just isn't that kind of a system. So the top of the heap for the style in question rules. STR for most melee, DEX for finesse & most ranged.

 

[5ekyu]

About the notion of which stat applies and so on...

Saw a post or article from a Dad wanting to roleplay with kids with homebrew system.

Had each task work like this:
Fogure out how you are doing what you want to do and choose two attributes that apply. Describe it in a way that makes it make sense.

So, thr could use quick and brains (dex and int) to sttike someone if they described it as figuring out their moves and striking at an opening.

It could be strength and cha if the described it as a feint or trick to let them slam.

Etc.

Same for any type of check, two separate stats if you could describe them applying.

Save vs fireball - wis and dex maybe if its "spot cover roll to it"

So, it could be interesting if a DnD 5e variant raised default DCs by 5 (guess) and allowed you to use modifiers from two abilities plus proficiency if applicable.

Some effects like saves might lock in ONE of the abilities used but leave others up for grabs.

Could work to mitigate some SAD vs MAD issues.

#Odd ideas before lunch.