Decorating Dilemma

I have a decorating dilemma and would love your opinion.   Our boys share a bedroom.  Currently, we have 2 sets of twin over twin bunks.  We are considering getting 1 set of full over full bunks, and putting a free standing full size bed in the room as well.  The room would sort of have the feel of the picture below, except the beds on the right wall will be full over full bunks and the bed on the left wall will be a plain full (no bunk).  I'd put a nightstand in the middle of the beds with a cute lamp on it. 

My reason for upgrading the boys to full size beds is to give them more personal space to call their own.  It will take away floor space in their room, but they don't play on the floor of their room anyway.  Since our family is growing, I want them to each have a space they feel they can retreat to when they need to get away, or just want to sit and play or read.  I feel like each of them having a full size bed, even if they are sharing a room with their brothers, will give them each a personal space to lounge.  So, here is my question.

Do I let them each pick out separate bedding they each like, or do I pick out a uniform bedding for all three beds and let them customize their spaces by hanging pictures and posters above their beds?

Here are two examples of neutral sets I found from Wal-Mart.  The red rugby is sharp and clean lined.  If you click on this link, you can see the sheet set better. 

This one is a nice brown plaid, which I also thought would create a clean, orderly look in their room.  3 boys in one room can be a challenge.  I want the space to feel warm and cozy.  I want them to each have wall mounted lighting above their bed for reading.

The next picture is one that I absolutely LOVE.  Of course, we would not do pink and green, but I like the idea of them being able to decorate their side wall.  I even thought it would be cute to paint the boys names on big pieces of wood to hang on the wall.  They each want a poster that could hang at the head of the bed-they want Army, Batman Lego and Star Wars Lego.  I thought framed posters would be easy to change out when they outgrow them.

I included this last picture just for an idea of creative ways they could decorate the space by their beds.

I would love any input you have.  My biggest desires are:

• Each boy has a space to call their own that they are proud of
• Clean, orderly area
• I want it to be cute, but I also want them to be happy
• I need help deciding about the bedding issue-3 different sets or 1 uniform look?