V1, Fnatic have a good chance at returning to Iceland. SEN on the other hand is probably 4th best team in NA right now(C9, V1, Optic are all looking better than SEN), Guard will probably not make it however they can definitely surprise us just like V1 did back in the days.
Vanity, V1, Fnatic, maybe TL, Vikings and KRU. Not sure about BR/LATAM, KR and APAC teams, don't follow/watch their games. C9, Gambit, FPX and Guard also have a chance of being newcomers.