Welcome to the forum BMW! You got yourself a nice camera there! Looking forward to seeing your photos.
I'd get the fastest possible card that is still reasonably priced. The problem with SD cards is the nomenclature used to describe performances: class 12, 40x, 45 mbps, etc... I still have a hard time figuring out what's what!
That being said, I typically like to have two cards of 16 gigs vs. one card of 32 gigs. Or two cards of 8 vs. one of 16. I like having multiple cards, because memory cards will fail from time to time. If a card fails, I'd rather lose 16 gigs worth of photos in it as opposed to 32 gigs. For the file sizes that you'll get with a 20 mp camera such as the RX100M2, I'd stick with at multiple cards of 16 gigs.
I've rarely ever taken any videos, so I have no idea how much space videos take.
My favorite cards are the Panasonic Gold. I also like SanDisk.