I actually think he's very different than Frattin.
What's struck me about Leivo, ever since I saw him in his first rookie camp right after we drafted him 3 years ago, is his hockey sense. The guy is just a natural - he's always taking the right angle to the puck, always has body in the right position to win and keep the puck, and just flat out knows where to be. The fact that he's fairly big, fairly fast, and has soft hands and a nice shot is a bonus as well. He's a very good possession player that never seems to be chasing the play, with a decent amount of skill. I'm not 100% but I do think he has 2nd line offensive skill, but I'm very confident that he has the all-around game to play a very good 3rd line role at the very least.
Frattin to me is the opposite - super fast, built like a truck, a howitzer of a shot.....but no hockey sense. Doesn't seem to have any idea of how to get the right angles or body positioning, and always seems to be losing the puck or chasing the play as a result.
And of course Leivo is way, way ahead of where Frattin was at age 20. Way ahead.
I like both players, but I don't think they're very similar, and I like Leivo quite a bit more.