My favorite eps were the ones with Ares, Caesar, and Borias. I love Marton Csokas to death, but he annoyed me as Khrafstar. I was a Joxer/Ares shipper in the day, so anything with those two basically. Also Bitter Suite and most of the Autolycus episodes.

That whole faux Christianity plot eventually ruined the show for me, though, and I stopped watching it in S5/S6, and I was really glad I had when I found out what happened in the finale.