Frankly, I'd be surprised (and disappointed) if Atton Rand WASN'T inspired by Ayn Rand.
First of all, the names are clearly similiar.
Second of all, the faces are clearly similiar.
And finally, the personality of Atton Rand is practically a near-match to the characters Ayn Rand idolizes and illustrates in her novels.
I' be super-interested in finding out if in fact Atton Rand was inspired by Ayn Rand.