Okay, so I'm a HUGE fan of the Elder Scrolls series and World of Warcraft lore. I'm choosing to make a vampire character based off of WoW; if any of you played WoW you would automatically think Death Knight or Warlock and maybe even a Dreadlord, but I've taken an interest in the Darkfallen class made up of undead blood elves enslaved to the Lich King's will. True Wrath of the Lich King fans will remember these vampires. Anyway, the Darkfallen is an all-around class benefiting from a Death Knight, Mage, Priest, Rogue and Warrior. Now back to the topic title: would it be useless to wear all types of armors because of their relation between Warrior/Death Knight (heavy), Rogue (light) and Mage/Priest (cloth)? And if this were not to be useless, should I spend perk points in all Light Armor, Heavy Armor and Smithing? Just curious if any of you have tried anything like this that I should know about before playing or just simply give me your thoughts.

*Also my thoughts on wearing all armor whenever I want is pretty much me saying, "I feel like playing as a Warrior now so I'm going to go sword and board and wear heavy armor instead of casting spells while wearing robes like a Mage." This class is needed for me to prevent myself of quickly dying with boredom playing one type of character or class; I want to do everything whenever I want it!

Go light armor.

Not sure what your asking... but "cloth" can be refering to mage robes/hood and clothing, which do not benefit from either armor perk tree. Also, you can do what you were asking about wearing heavy, light, or clothing based on what suits you at the time.

Yeah! What I mean by cloth is going into Alteration for the armor cap, I guess I should have mentioned that, lol. But would it be useless to spend points in Light Armor, Heavy Armor, Smithing and even Alteration? Just like if I were to spend points in both One-handed, Two-handed and Block.

I think it would be overkill, you're spreading yourself too thin with all those skills.

As far as straight up stats and game mechanics, light armor is best. Still able to hit the armor cap, "weightless" perk is at level 50 (instead of 70 for heavy armor), and the lvl 100 perk "deft movement" is vastly superior to "reflect blows" of heavy armor (it only reflects base damage, which is almost nothing in the grand scheme of things).

Alteration and heavy armor are still perfectly capable armor skills though. Alteration can hit the armor cap with the master spell "dragonflesh", and of course allows access to many other useful spells and passive abilities (the magic resistance perks are especially good). Heavy armor provide noticeably more protection early in the game, and is the only skill that can passively increase your uarmed damage.

Investing in all three armor skills is rather pointless and does not provide much benefit. Light armor is probably your best bet if you want versatility.

Look and decide which Armor looks best on Your character and invest in the Skill it uses. I do use Alteration for the potential Magic Resistance and Absorbtion it offers as the Skill improves on almost all of My characters.

Difficulty level can make a big difference in which Perks are needed for an Armor Style. I do not need any Perks on Novice or Apprentice, at Adept or higher Armor used begins to be significant in surviving Melee battles when outnumbered or having to survive being pinholed by an Archer while needing to kill a Mage quickly.

Play however you want OP, it's not gong to be the strongest build, because most of your perk points will be in two different armour trees apposed to one armour tree and an offensive skill. But try it out and see if it works?

My pure mage is a level 92, she never wore any kind of armour nor did she hold a weapon. Since Helgen till what she is doing now (becoming thane of all the holds), no enemy was even 20 feet away from me, was dealing lots of damage with shock spells and conjuration.

As you can tell, mages always keep a distance, will only use a dagger in melee range or when their magicka is low. you should do the same, take them out before they even have a chance to come close.

PS: No sneak as well, heck her sneak is level 35-40 (hit legendary several times with destruction/alteration/conjuration though), smithing is 100 and no perks, its for making cash.