For generic nobles quarters, I like the model in Tyson's book with a row of 4x4 rooms connected by 1x1 hallways with doors. For more value, I go for 5x5, so when it's all smoothed and engraved, there is more chance of multiple masterpiece engravings in it jacking up the value.
The order, from the hall to the innermost room: office, dining room, bedroom, tomb. In the office, a table, chair and cabinet; in the dining room, a table, chair and chest; in the bedroom, a bed, chest, and weapons rack; in the tomb, a coffin and armor rack. Throwing in statues can always spruce up the place, and you can also add a room just for that.
Another thing I like is, if I can manage it, at least one waterfall in one of the major rooms. If I have a row of suites like this, all in a line, it's a lot easier to engineer this. And if I can't at the time, having them organized makes it easier to do it at a later time if I live long enough.
Think of it as McMansions for dwarves.
Also, I keep at least one stockpile just of masterwork furniture (at least once it's being produced regularly) so that especially important suites get at least a masterpiece for the central piece of furniture that defines that kind of room. If it's really important, make every piece of furniture a masterwork. Artifact furniture is, of course, especially good for this.