hey dude, i dont like that blue you used, theres too much of it. you need something more subtle for a overall colour, maybe a lighter tint of that blue or something more pastel. and keep that blue you have for title heading or something.
I guess your flash banner is really up to you. You could have your characters running around playing jokes on each other .(eg spy vrs spy) of just doing funny things. It all depends on the character personality of each character.
i second the blue…it is much to much…Also the site is to HTML-ish. I knew immediately that it was all html no images and what have you.
For your banner jazz things up maybe some sound a lil more color. What I do when I get stuck is cruise some cool website sites. For inspiration or look thru magazines. check out www.coolhomepages.com and www.netdiver.net . Notice I said inspiration not rip. But you have a good foundation or framework in the HTML just jazz things up.