A few more frames for the sign might do it good (it movement speed isn't constant) and the cloud shifting so quickly and then slowing down is a little strange (I have no idea how long the banner is going to be up before they game starts, but maybe make the clouds move at half that speed and add another one to the cycle). The stars fit in pretty well and I like the colors and the lines you chose (give me that old game feeling, which is good).

Hope your game development project goes well. Let me know if you need any voice acting, beta testing, or script writing done for the games. I'd be happy to help.