Sellers do at times need to boast the value of their property, but where should they put that money?
It all depends largely on what a buyer is looking for.
Living in Hernando County (Spring Hill, Weeki Wachee, Brooksville and Hernando Beach), Florida, we would think that most people want a pool. As a realtor who lived in NY, I am surprised at how many people don't want a pool. The reason being if they are only doing it as a vacation home and don't want the maintenance and expense of keeping up a pool. Also some families with young children are afraid of the possibility of a child falling in.
Should you add that media room? That is a "buyer specific" room and my opinion is that most buyers would prefer another bedroom to a media room. If they want a media room, it is easier to convert that, but if you are thinking of adding on, make it usuable space like a bedroom.
Landscaping -you don't have to spend a fortune on landscaping, but the grass needs to be cut and bushes trimmed. Put a few flowers for color which will give curb appeal, but you don't need to go buy statues, etc. Keep it trimmed and neat!
Other tips will follow.