I tried the official solo rules, the ones that come with Fall of Rome basically. First session I thought they made it easier, which is something the game really doesn't need. But I lost the second one. And I really like to only hold one hand of cards.
It would be good enough to have it as PnP. And it's very light. But I play it occasionally, on "heroic" difficulty. And if you like the gameplay of Pandemic (which I do), this one gives a nice quick fix.
Hard to say if it's worth it for other people. I like having some options in light games as I'm often tired by the time I'm ready for some playing.