By that I mean, do you say "I'm going to be a sword and shield person and nothing else," or do you allow yourself the ability to alter your build if you feel it fits the story?
Static.
Unless you're playing as a character who is a jack-of-all-trades type.
For instance, with one character I originally decided I wasn't going to so much pick up a two-handed weapon, let alone use one, but after a near death experience with a Draugr that liked to disarm me, I found myself killing it with an Ancient Nord Greatsword out of sheer desperation. After that, I paid for some training and gradually started trying to learn how to use it in actual combat.
First that seems like an illogical restraint to put on yourself.
I think I have a different definition of "role" playing than others. That decision on your part sounds more like a house rule than a role, IMO. I look at "role" playing as if I was acting in a movie. You wouldn't act the part of Spiderman like you were the Hulk, right?
Establish a role or boundaries for your character and try to stay within them. Constantly ask yourself: would (x) do this?
In your experiences have you ever seen a character who would refuse to use a certain type of weapon when they were in a life/death fight?
That's like saying a highly trained MMA fighter wouldn't use a rock/stick if their life depended on it and then afterwards turning around and abandoning their martial arts training because they won a fight using a weapon.
Consider yourself lucky and think of ways to avoid a similar situation. Take the advice of bandits and carry a dagger if you're tired of being disarmed.
I've also joined the College of Winterhold with characters who were initially opposed to magic when they failed to protect a character or couldn't heal them from not having potions on hand.
That might be the limits of your character.
You can't save everyone. Being better supplied wouldn't help?
If you choose to go into a dungeon with followers and you only bring one or two potions for them and they die...that's on you.
You don't need to learn magic you just need to bring more potions. If you bring a ton of potions but run out before you finish the mission...that's on you too. You just have to fight smarter and conserve your potions there's no need to learn magic.
There are other examples I can list, but I won't for now. Just curious as to how you go about it.
My characters NEVER have uber armor ratings (my average AR is @85). I NEVER wear full suits of armor either. I NEVER use a shield. I NEVER use enchanted weapons.
Having said all that...I NEVER get engaged in sustained melee either. I'll be crushed. I accept that as the limitation of my character. No matter how many melees I lose I would never become a walking tank. I just try to fight smarter and use skill/technique to replace power.
I don't use companions/followers, besides the fact that they're annoying and get in the way all the time, mainly because I can't heal them.
Those are some of the established/accepted limits on my characters, IMO, it makes the game more fun because it forces me to think my way through some situations. Instead of being a potion popping tank hacking my way through everything.