Along with the Smart Cover, I also bought the 10W USB Power Adapter that includes a 6-foot-long power cord. I can use the iPad while charging it without having to pull out an extension cord. I put it in a drawer in the living room right where I'll plug it in when needed. Perfect!
You forgot the Digital HDMI adapter as well as the Dock Connector to VGA adapter as well as the extra power adapter...
That being said, I am just reusing my red smart cover from iPad 2 as well as the above accessories. I did buy a camera connection kit but have yet to use it.