I had a very similar nexus and chose Okoye. She is a fantastic attacker, and easy to use. Zola is a solid defender, but definitely has counters. Also, his rotation is apparently a challenging one to get the timing right on to maximize damage. So, since I’m a bit of a scrub I didn’t feel like I’d be able to take full advantage of him as a dual threat. If you are a top tier player I’m sure that wouldn’t be an issue.