Sounds like you should just multiclass.
why have paladin you can just multi-class?
What would be the benefit to turning it off- unless is turns off as part of being a penalty due to the power of the class.
I think it may need some more ideas to help focus what you are talking about, but like the idea of having some sort of symbiote like Spider Man and Venom before Venom went all killer.
I was going to add that it lets you blend in more as unlike other unarmoured class it does not use bear asking but it is more flashy, so yes think kind like venom in that you with the armour on is very obvious.
I'm totally unclear on what the class is you're talking about, what makes it new, and what, if any, unfilled archetypes it enables. Your post reads to me like you're describing a warlock. You mention the power dynamic being more equal than a cleric or warlock, but I'm unclear what dynamic you're referring to- there is no inherent power dynamic built into the cleric or warlock, and only a few campaigns seem to impose one.
warlock and clerics serve a higher power, here you need them and they need you as without them your a sub-par fighter and without you can't cast properly and can not be developed further.
as in you can disagree and not be vaporised, I no some campaigns do not care for the roleplaying bit of serving something else with a will but that also does not matter here.
as otherwise cleric and warlock should be the same class.
there is no gifted power both you and it work together but it can have an interesting interpersonal relationship as much as the player and dm both want it.
en.wikipedia.org
Maybe something like a totem shapeshifter fighters, in the middle between the shifter class by Pathfinder and the totemist (shaman) from 3.5 "Magic of Incarnum".
that was an idea for a subclass.
It sounds like a class that borrows elements from existing classes, but doesn't really have a unique mechanic of its own.
It might be a good idea to think about what role is currently left unfilled in an average D&D adventuring party, or what unique mechanic would really bring something new to the table.
I am trying to think of a more exact mechanic I was thinking something controlebased as no martial or half caster at present can really add that.
technically no role is empty nor has one been epty for a while but people like half casters and have longed for a third one and it is desirened to be more customizable and versitle than ranger who is mostly range damage or paladin which is all tank.
this is mostly a magic skirmishers but can fill he other roles depending how you build them so you could have three in a game and no one competes.
I'm not 100% clear on how they get their magic. They gain it from being boned by a small entity?
I am proberbly explaining to badly as typed text is not what I am good at, think less master servent and more three legged race, you and the thing grow and build together it is more or less literally fused to you and as you grow stronger it does as well. slightly high concept but made to at lest be refluffable to other settings as needed.
And they are half casters, but can be specced for str or dex, which are not caster attributes...?
but they are the need atrrubutes of paladin and ranger recitively for there weapon use.
no idea on casting stat yet but not cha as that has sufficient number of classes.
