Actually E-- figuring out what kind of cigar you might like is a lot like wine. The analogy is really a pretty strong one. I tend to like Merlots and Cabs. If I'm trying something new out, I'll try one of those. Unfortunately, there examples of both that I don't particulary care for. So beyond the first discriminator (is it a merlot or a cab?) I look for ones that are described as having flavors of wood, oak, or spice. It tends to get me a little closer to the target. You can do the same with cigars, to an extent. The biggest difference is that all cigars are a blend. Those Oliva O's are made with a dark habano seed wrapper and has Nicaraguan fillers. Cigar Afficinado describes the whole smoke thusly:
”This cigar has a gorgeous color and a lush wrapper. It draws well, showing cedar, toast, leather and coffee notes. A complex and balanced full-bodied cigar.”
Those are good jumping off points when looking for another cigar. Though I've had a couple of "lighter" cigars this week (The Olivia and the previously mentioned 5 Vegas) I tend to lean more towards really dark and heavy smokes. So I went and asked a friend/co-worker who told me about the Olivias what else he liked. First and foremost, he said that those were his favorite. After that he said he really liked a Partagas Black Label (I had to google that one-- but it looks like it might be more my taste). He also likes cigars from CAO and Padron. Mind you, those are both brands that have a lot of different types of cigars in them, so look for those leaf or flavor queues when buying them. I also had a ghurka warrior awhile back that might be to his taste. It was excellent. The bottom line is, unfortunately, that you just have to try them out. Some will be great, and some will be "meh". If you can buy singles, go for it. If you're stuck getting them in a pack or a box, there are lots of active cigar trader forums out there. Because really, we all sometimes buy cigars we don't like.
One more thought, some cigar forums like to "bomb" newbies with a variety of cigars to try out. If it's really something he's interested in, I suggest he find a forum and introduce himself. He's likely to make a few new friends and get some new cigars.