Personally, I like your second more finely cross-hatched shadow on the cardinal. Perhaps you may even want to put some washes over the hatching. Since you start out with the pen and ink, I do think it is very helpful to put something down in the shadow areas.
I think the pen and ink works especially well for capturing delicate details, like the feathers and fur, and the fine grasses in the background of the cardinal.
Your cat reminds me of some of the illustrations done by Beatrix Potter, also using pen and ink plus watercolor. Take a look here