Re: Armor restrictions

Mods may not be your thing, but if they are: https://www.nexusmods.com/baldursgate3/mods/58

That unlocks a whole lot of already-implemented content, including several weapons (up to +2 supposedly but I have only seen +1), several armors (up to +2), and some miscellaneous gear. It also adds random chances for items to some chests and tweaks the vendor lists so they may carry the items.

Still completely true to 5e as implemented by Larian - it just unlocks locked content.