Great update A lot of things to think about for sure.
One thing bugged me though:
I get what you're thinking with this, but I really do not want to end up with World of Warcraft, where I have to run around with 4 full armor sets in my backpack for specific situations. Please do not go this route -- when you've found the best armor your character has access to and can currently use, let that type be the best for all situations.
If you must have this concept of swapping armor for specific situations, then support it. Don't have us lugging around 800 pieces of situational gear in a big mess along with spider eyes, vendor trash and that quest item you're not sure if you're ever going to use. Instead make alternate loadouts (for example), such as two tabs in your inventory/character UI that you can swap between by the press of a button - and if you really feel that situational gearing should be a feature of your game, don't penalise people for it. Either balance weight allowance around it (if you have that in your game), or make only the heaviest set count.
Just my thoughts on it of course, others may not agree.
All the rest of what you wrote sounds good, and personally it doesn't really bother me how you choose to name upgrades. Whether it says "+2", "Exquisite" or "Adamantium" matters little to me. It doesn't change gameplay, only perception of it (which is more important to some than others). As a rule I'd say that "+2" breaks immersion, but we're so used to it by now that most of us don't really notice it I think. In our brains it largely computes as UI information now, rather than something on an actual name tag in a store.
With regards to wizards wearing plate, that is GREAT in my oppinion - if you don't allow multiclassing. If you allow classes to mix so that you have a "fighter wizard" then there is little reason to have pure wizards wearing plate. But if you're not going to do class mixing, then it would be awesome to be able to make a type of wizard focused on close combat with heavy armor; A battlemage spec, basically. I'm totally into that In arcanum I almost always end up playing a battlemage with sword, spells and big ass armor.