Kree and Skrulls are both basically different flavours of asses. Like the Sontarans and Rutans in Doctor Who, both probably just view Earth as a battleground. Clearly though the Skrulls are being established for Avengers: Secret Invasion in the next couple of years...
Nova and Shang-Chi both seem like decent choices for new solo franchises at Marvel. They’ll probably want to be selective about what ones they stick on the screen and what ones to have on TV or on Disney+... Shang Chi could have suited as a decent replacement for Daredevil or Iron Fist...