I realise that after Steel Plate, most of the heavy armor looks rather childlike. I even began to get sick of Daedric armor; and Ebony Armor slopes too low, especially around the neck area.

I duly switched to Steel Plate for the rest of my adventure after completing the MQ. It looks pretty good, and it makes the game more of a challenge since enemies do more damage now. I'm thinking of degrading down to Banded Iron Armor, I really love the look of that set.

Does anyone else wear armor for cosmetic purposes?

Yeah, I used Scale Armor over Glass. Besides it's noted that the max armor you can have is around 600. I think most armors can reach that with the right amount of smithing and perking.

I use Scale or Studded, Glass looks lulz, pretty but lulz Daedric is too much and just doesn't feel pratical to me.

I do. Plate steel here, too. I make followers, when I do have them along, wear the lower-level armour, too.

I much prefer the rugged, simple look of the iron and steel armors and weapons over the fancy Daedric stuff.

I hate the way upper level armor looks in TES games, it's always so dorky.

My favorite in Morrowind was the Chitin armor, it was odd, but somehow fitting. I'm trying to stick to steel, and hopefully find lots of smithing items to improve stuff more so I don't have to use the Daedric etc. when the time comes.

In Oblivion it was quite sad after I got the full Daedric set, so for a huge part of the game I just ended up looking a Dremora or something super evil, with the helmet on

Steel / Skyforge Weapons look the best as well. Steel/Skyforge dagger is the only dagger that looks like ... a dagger. The two handed sword and war axe are also among the best designs.

As far as armor, I'm picky and haven't been able to find any that work for me. I like full coverage, the various sleeveless armors don't work for me since you can't wear clothes under them like in Morrowind. I also don't like them to be too flashy. The thieves guild armor is closest to acceptable but the hood is too low and it has bracers instead of gauntlets/gloves which I prefer - Skyrim is cold and I play a Dunmer not a Nord. I just wear robes with a mod that makes a craft-able armored version that have armor rating equivalent to leather armor.

The dragonscale armor is OK for my taste. With only 1 in heavy armor the daedric gear is not even an option, and all heavy armors are ... Well, too heavy.
As followers are skilled in heavy armor I give them dragonbone instead because they don't wear the dragonscale over their default steel (I mean the housecarls)
but no helmet for the followers. I give them crowns because I like to see their face.

In morrowind, I liked the chitin too, except the helmet. But all helmets were weird in Morrowind.