Crowds should be low both days with Sunday being slightly higher first week of Nov. 2nd week November 12th is a holiday and would see higher crowds on the 11th.
That said, Sea World is the place to go on a higher crowd day. It is mostly shows and exhibits. The show stadiums hold more than the shows at Universal so as long as you arrive a bit early you'll have no trouble. Even on crowded days the lines at Wild Arctic and Journey to Atlantis are short. Lines at Manta can be long afternoon and evenings so ride early. Shipwreck Rapids has long lines on sunny afternoons, otherwise short.
Universal can get very long lines on busy days for Simpsons, Tram Tour, Mummy and Jurassic Park. Early Nov. except for Nov. 11th should be light crowds.