Vael
Legend
I think there's not too much more space when talking subclasses, except for Psionics. That'll open up a large area, as, aside from the Psion/Mystic itself, virtually every existing class could conceivably have a Psionic subclass.
But aside from that, the other large untapped well, and I'm not sure how to tackle it, is Monstrous PCs. Things like playable Vampires or Lycanthropes. Or more exotic races like Gorgons.
Although, here's a few subclasses I've been working on:
Circle of Stars Druid: Basically an Astrology and Divination focused Druid. I'd grant them access to a few Cleric divinations like Augury, but they need a bit more of a niche. These are kinda the mystics that read the stars for omens.
Brawler Fighter or Barbarian: Give non-Monks some access to unarmed combat. Grappler-wrestler combat style.
Blue Mage Sorcerer: This Sorcerer has the ability to mimic and copy spells they see cast.
But aside from that, the other large untapped well, and I'm not sure how to tackle it, is Monstrous PCs. Things like playable Vampires or Lycanthropes. Or more exotic races like Gorgons.
Although, here's a few subclasses I've been working on:
Circle of Stars Druid: Basically an Astrology and Divination focused Druid. I'd grant them access to a few Cleric divinations like Augury, but they need a bit more of a niche. These are kinda the mystics that read the stars for omens.
Brawler Fighter or Barbarian: Give non-Monks some access to unarmed combat. Grappler-wrestler combat style.
Blue Mage Sorcerer: This Sorcerer has the ability to mimic and copy spells they see cast.