Karen Gillan has done very well in the MCU. In the original script for Guardians of the Galaxy Nebula was supposed to be killed, but Gillan impressed James Gunn so much in her audition that he substantially expanded the role, rethought Nebula's potential and made her relationship with Gamora one of the key emotional centres of the franchise. The character then made it into Infinity War, surviving Thanos' Snap and looking as if she's going to play a key role in Avengers: Endgame.