I know a lot of Ugandan Zions, and a few Rwandan ones as well - I personally associate it with Christians, though that's probably because the only Jews I know called it are Israeli and pronounce it "Tsee-on" as a result.
You say you grew up religious but aren't now: if that was Jewish religious, go for it. If it was Christian religious with an African background, go for it. Any other Christian background, as you no longer practice, I probably wouldn't. If you like the OT vibe, how about Noah, Abel, Elijah, Elisha, Nehemiah, David, Zachariah, Ruben, Solomon even?