Welcome Obbles! Have an upvote! Also, a warning about cookies.
I'm KnightRadiant. Nice ta meet ya. I sort of did the same thing you did, in reference to reading that is. I discovered the cosmere after reading the original Mistborn Trilogy, Era II, WoK, most of WoR, and Elantris. That kinda sucked. I also discovered it through a kind of round-about way. I was reading Secret History at the same time as I was reading WoR, and noticed the name Nazh in both books. Hoid didn't tip me off, nope it was Nazh and his unique name. Did something specific tip you off to the existence of the cosmere?
I basically did the same thing you're doing after reading Stormlight. I had to find out anything and everything
Anyway, see you 'round the site! If you have questions, feel free to PM me or just give me shout.