Personally I think the site should be contained within the header width, having too many banners not only takes longer to load but is a big turn off to potential sign ups.
I would try to feature maybe 5 casinos and special offers and have the rest listed on a side naviagtion bar and make the content on the home page more about what the site is for.
It needs to be easy on the eye and flow nicely as it’s read with the aim of telling someone why they should sign up.
perhaps changing to simple free template may be a good idea something like this: http://www.gamblingtemplates.net/template72/
Good luck