This is my current standard layout for the bedrooms.
For the peasants it is 3*3 with 1 Bed, 1 Coffer and 1 Cabinet, in "blocks" of 5*2 rooms surrounded by 3-wide corridors.
.......................
.==#===#===#===#===#==.
.|...|...|...|...|...|.
.|...|...|...|...|...|.
.|.B.|.B.|.B.|.B.|.B.|.
.=====================.
.|.B.|.B.|.B.|.B.|.B.|.
.|...|...|...|...|...|.
.|...|...|...|...|...|.
.==#===#===#===#===#==.
.......................
The Administrators and most nobles live in 9*9 combined quarters (bedroom/office/dining room) with 1 bed, 1 table and 1 throne and all other junk they might want.
====#====
=.........=
=.........=
=....T....=
=....C....=
=.........=
=....B....=
=========
Have not been allowed to have the King arrive, did notice a message in noble screen that he/she was due to arrive soon, but quit with the fortress before he/she arrived.
The highest noble I have had so far in a 140 dwarf fortress was a Baron which was promoted to Count 1 or 2 months after he arrived.
For the king I was thinking about a 13*13 Combined room or 3 seperate 9*9 rooms (or bigger depending on my mood)
I did notice some annoyance from all the Nobles for having a lesser room then my administrators, appearently their rooms were completely Obsidian and the rooms I gave the nobles were part Alunite.
I was actually tempted to relocate the DM to better quarters because he/she is the only usefull noble I met so far. The Baron/Count can stay in the Alunite room...