My issue is with how they've pigeonholed every martial class's turn into "I swing with my weapon".
To be fair, there are a number of thrusting weapons - one, the rapier, is even an optimal weapon for many builds - and excellent ranged options, as well. Besides, there is no 'martial class' that cannot also use spells to some degree in at least one sub-class.
I would prefer if battle master was rolled into the fighter class and there were further archetypes that provided unique abilities / benefits (as current archetypes do) and then the player could select from the list manouvers and list of archetypes to make more interesting martial characters.
That'd defeat(npi) the purpose of the 'simple fighter' concept.
Adding more spells quite clearly complicates the "weapon" of spellcasting by virtue of adding more options.
Well, sure, and spells are more complex and varied than weapons in the first place. Most of the game's complexity exists in it's several magic systems, afterall.
The thing is, if you want options an complexity, you play a full neo-Vancian caster like a Wizard, Cleric, or Druid. If you want a simple character, you play a Champion fighter, slightly less simple, a Berserker, BM, Thief, or Assassin. The other classes and sub-classes (and optional Multi-classing) fill in the continuum between, if not exactly evenly.
Not to mention that each spell is it's own self contained mechanic with varying levels of complexity. Imagine the outcry if there were a similar number of martial maneuvers.
Remember the outrcy. It started in 2008 and hardly let up for years. You can still here it echoing in the Warlord threads.
Is there some reason I don't know of that you can't just make it a "Sunspear"?
There's no reason you can't, other than tradition, and expectation. 3.x, for instance, had item-crafting rules that allowed you to graft any enchantment onto any weapon. You could have a holy avenger whip or a life-stealing sap or whatever. 5e doesn't go there - though it doesn't tell you can't go there, it also doesn't point out that there's a 'there' there for you to go to.
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