I would center it up some.
Put the menu more to the left.
make the banner a little bigger or set it off to the left and put a slogan or your motto to the right.
I would also like to see a page about you. Not necessarily something lengthy but just about how you got into it maybe your favorite herps.
Also maybe a phone number so your prospective customers can talk to you. I understand you probably have a "day" job so that may be kinda hard to do. I like to talk to the people I am doing business with over the phone.
Then in your collection maybe have a favorite picture of the animal you are talking about and a link to a page about that particular animal or morph.
I would also like to know about the individual species, a scientific name and a little synopsis about the species. I also like to know about how the morph was proven or discovered.
In your section about animals you will be producing maybe have pictures of the animals. If you do not have any or have not produced any maybe find some representative pictures. I would worry about putting up representative pictures in the fear of some one thinking you are trying to steal their photos.
I really like the way Adam Wysocki's web page is set up. I also like the way your web page is set up. I like the navigation of your page but I like the visuals of Adams page.
I know I have thrown a lot out there for you to think about I hope it is not confusing and it is helpful to some degree.
All in all it looks great and I think you have done a wonderful job. If you left it as is it would still be great.