Health - Essential.
very wrong, i am level 30 and have yet to put a point into HP and im not planning too as im mostly sneaky/illusion assasian its fun to know that if i am cought im generally road kill in one shot unless i do some super duper manover tactics. (master difficulty for reference)
I don't think it is very wrong to say Health is essential really, I've found most builds and character designs value Health mostly, it is possibile because they don't want to be one hit kill like sometimes you experienced. On a side note, congraulations that your play style would not allow to be hit at all most of the time.
Magicka - Useless, at end game as you would be able to cast free spells via enchanted items, no Magicka required.
if you exploit the games magicka cost reduction system (which isnt difficult) then you could call it useless yes but the majority dont exploit it in my experence thus it is required as a mage.
Casting spells free of Magicka is not an exploit, it's not a bug but part of a game desgin, if it was to be considered as an expolit, then stack your items with the same effect would also be considered as an exploit by that theory, I guess it's a personal thing, you can consider it as an exploit as you do.
Stamina - 'Not bad to have', that usually means rubbish, the main value of Stamina seems to be Power Attack.
hmm from my personal expereience i would love to have more stamina but i have again yet to put a point into it as i am first building my Magicka up then i may invest some inside of stamina for Bow-Zooming and Bow-Bash kiting.
Good on you, but for your run and gun style, I would imagain you have more say on the value on stamina.
so dont perk or use them if personally there viewed as too powefull. all i am personally using is frost(slow) and magicka/stam/illusion reducing regen enchants as im a S4 vamp thats pretty much required (the magicka one) for my playstyle
I've said "so powerful', not 'too powerful', I have no problem to be too powerful as long as it's legit, in most RPGs you would find you could always be too powerful.
not really no a mage will need mana unless your exploiting and probably a good amount of HP too (especially if your using robes)
I won't be investing in Magicka, I will relying on enchanting.
I would love to hear more about the importance of stamina.