You can do just about anything you like! Just make sure pieces don't run into each other and keep track of where you are going when you number your boxes. It really is not hard. Take a look at some of the more complicated paper piecing patterns, and watch how they do them. You will be making your own very soon. I just did a spiky elongated circle from combining a couple patterns I had seen.
And converting a pattern to paper piecing is pretty much the same process of watching what color comes next. I do it all the time with patterns that have a lot of triangles. , which I have trouble with if they are not paper pieced.