It would take a bit of practice, but I think that they should have a lot to offer for new players, as it's an easy environment to just keep playing games in without fear of coming up against super-complicated or powerful decks.
In terms of complexity, I've tried to include a good mix of simple and complex mechanics. If I had to rank the decks roughly overall, I'd probably go with something like this:
Beginner-friendly: 1, 6, 7, 11
Somewhat beginner-friendly: 2, 3, 8, 9
Not beginner-friendly: 4, 5, 10
But then again, that's quite subjective and difficult to gauge, so don't let one deck put you off if you don't like it. I'd be interested to hear other's thoughts on that too.