Re: difficulty levels - it depends, in my case.
For most Western RPGs, the storylines are generally pretty weak, fun at first, yes, but if you have been playing 1300+ of playing a game, lets stick with Skyrim, you know the various fetch quests and others that make up everything. So I'm looking for a challenge. Yes, you could not try to be a stealth archer, but putting in a difficulty that cuts your damage output by a quarter and increases enemies by three, makes you rethink how you would approach certain bands of enemies and other situations.
Also it makes me look a lot more at alchemy, magic, enchantments, crafting and companions, and develop them properly, whereas at an easier mode, you could quite easily just bash/shoot enemies solo, pick up levelled loot and practically ignore all of those factors above.
Also (I'm hoping) that changing the difficulty so much means that it takes much longer for me to get to the level when I damn near invincible, which usually happens mid-game for me in Bethesda games.
Yes, I also have Dark Souls, and really enjoyed the hard bosses in AC: Odyssey, so going Legendary in Skyrim seems natural to me