Likely to be rebelled against. Ned was a Lord from the remote north who in truth was a second son. The realm just saw one king toppled who's to say the southerners would really accept him as king

To me Roberts claim wasn't about the divine right of monarchies but more about that he had the blood of the dragon lords who had ruled for the prior three hundred years. But yeah it's all moot now

And ur right, it all comes down to who can make it happen in that moment. That was renly's whole thinking. I have the army and the support and ppl like me so there

U see that with Jon and Sansa this last ep too. Sansa by rights should have been heralded as Queen of the north but the gathered ppl simply liked and respected the bastard Jon snow more.