*****************************
Sorry, you really need to read my response because I just went through this and have insight I don't think others will offer.
IF you get a smart cover, you will need to either get a skin to protect the back of the ipad, or a TPU case or a shell. Reason: When you fold the smart cover back, the front of the smart cover (with no microfiber lining) is in direct contact with the bare metal of the ipad. If you have ANY debris, it may cause small pits/scratches in the ipad. I found out the hard way, but luckily I had my ipad replaced for other reasons.
My recommendation is to just get the smart case. It is the best overall solution for light-weight, worry-free protection/use. Even with a skin + smart cover, you can really just drop it in your backpack worry-free. Some edges are exposed. Even with some shells and cases, they leave some areas exposed.
The Smart Case covers EVERYTHING, from buttons to even the area around the speaker and lightening port.
The few downsides it has are that it adds a little more weight to it, and some covers don't lay flat.