That is about it for the content, believe it or not; it is direct and straightforward without any fluff or nonsense. You are simply covering each detail so the seller knows exactly what the buyer intends to do. Having an informal letter of intent also allows for easy negotiations.
We find exactly the opposite to be true. If you were to go to an unknown area, would you want a map of the area? Well that is exactly what the LOI is: a map of the major deal points. In today's busy world it is important to be sure two parties are going down the same road and in the same direction before spending too much time working out all the details of a transaction.