Lets see...Yes ...
Add the CSS for at least the most useful modules as static CSS because formating for most modules is more or less ugly .
A multilevel dropdown would be nice.
Maybe you should check CK-Editor module , to add CK compatible editor.css and .js.
As sooner or later we will change to CK. (many already changed to CK )
You schould add a premade photoshop mask for the fadeout effect of the slider images , so its easy to make images that fit exactly (maybe even a mask for Gimp).
You ever tested premade joomla or WP Templates from template monster ?
They always have a full CMS whith all necessary modules and the template packaged into their packs.
So its just a no brainer , just unzip, install , ready , no need to add anything.
But maybe thats overkill