I can't believe an MCB M3 has been for sale since August! I think the price is pretty fair too. If I was in the market for an E90, there's no doubt in my mind I'd go with an Individual color over a standard one.
I guess the only thing I can say is to take way more pictures. Engine bay, rear seats ect... That surely can't hurt. Good luck to you! So sad to see her go.
P.S. I think you should keep it