The colors in the second pic are great. Do you have a tripod? Hand holding .4 sec the picture is not going to be tack sharp like you want.
The composition and idea of your pic are great! Good job of "seeing" it. Can you go with a larger aperature than 5.6? Like F/4? Or try to bump your shutter up a little bit.
A tip on hand holding, if your focal lenth is 70mm then the minimum for hand holding would be 1/70th. You didnt say what your focal length was. If you can adjust either your aperature or your shutter, or if you have a tripod, your picture will be much sharper.