I'm sure you have already considered this... but just in case.
Using a simple javascript snippet you can have the Front Page photo "randomly" change between many different choices.
Here are a couple of links to example scripts:
http://www.javascriptcity.com/scripts/img/simage3.htm
http://www.draac.com/random-image.html
I love the front page photo's and I think it would be neat to see a random photo everytime I visit!
P.S. The script samples I provided make you "hardcode" which photo's you want to randomly change right in the script. I'm sure there's probably one out there that would let you specify a directory to pull the photo's from as well.