Ah, never too early to plan IMO :)
We did a pink and green whale theme. It turned out really well, there was so much cute stuff online, especially on Pinterest. We ordered a lot of the supplies online too, and then made a lot of stuff we found on Pinterest.
I think this year, we are going to do a sock monkey theme. It won't be a huge party like her first birthday, but I'd still like to do a theme. (Let's face it, it's just fun!)