well. i agree. keep it simple. dont put bunch of graphic. dont go neon.
dont use emboss and bevel... dont made it to dark dont made it to light.
here is vb variant theme for smf which i extremly like
OKnet.Ru : Форум - Главная страница
click on blue version
also i like cleant theme
with icons for subforums for example
or this is great to, even i dont like sidebars