A cool weapon/armor set would be Obsidian. Obsidian is really cool there should also be spears for every weapon set as well. Back to Obsidian, it is this black molten glass sort-of. The ancient civilizations used it to make sharp tools that were needed. Try to consider this idea, thanks

there are a lot of weapons and armor lore wise, i'm not sure if obsidian is in it but as long as it follows the lore i am okay with it.

there is already glass armour. It is the Tamriel equivalent to obsidian (a volcanic glass)

Ebony is also a volcanic glass/metal that is black like obsidian

As suggested above, there are already a variety of sets from previous TES installments that meet your expectations. There should be more than enough variety in armor sets alone if ZOS just takes inspiration from the various sets BGS has created over the years.

Also since the game is so far back in the timeline ZOS can be a bit creative with some never before seen armor types and materials from bygone eras. Who knows what they were wearing a thousand years ago. I just hope they avoid going nuts with any outlandish styles and spikiness. Can't stand spikes! Just make armor and weapons functional looking to a reasonable degree.