If you are itching for more content in Awesomenauts you're in luck as the developers have just released a Level Editor along with Steam Workshop support. In other words, you can now create, share, and easily download all sorts of mods and user creations. There isn't a ton of content available right now given that the Level Editor just launched, but there is still a surprising amount of custom maps out there for you to mess around with.
On the other hand, if you would like to take a crack at modding yourself you'll find that the official wiki has extensive guides on pretty much everything you need to know. And if you can't figure something out, there is also a dedicated modding forum you can find by heading over here.
Besides mod support this update has also added Deadlift as a playable character. He is a young Bovinion (I think you can already see where this is going) that has spent his entire life in exile, training every single day in the hopes of taking revenge on the cowboy that wrangled his entire race - Sheriff Lonestar! Despite that description Deadlift is a tanky support character that primarily excels at absorbing damage, though I wouldn't recommend underestimating him in a fight.
There's also a whole bunch of other features, bug fixes, and balance changes, so if you're interested in all of the details you can find what you seek over at the official forums.