XP: Need help with our Den space (with PIP)

Fields*of*Gold

Ok.  I'm struggling with our "Den" space (our house is split level with the bottom level just one big room with laundry/small 1/2 bath that leads into the garage.

I want the room to serve 4 purposes:

1.  TV room (where I want to shove my teenage boys to watch tv when they are older and care about tv/video games)

2.  Guest room (b/c it has a seperate door, entrance via garage and 1/2 bath) - the only guests we get our my mom 1-2x per month for 1 night or my inlaws for like a 6 week period of time. 

3.  Play room (behind the couch area? where the two ugly chairs are in the pics below)

4. Computer/homework area (work into area designated for play room?)

The room is 19'x11' rectangle (for reference, 19' is sliding glass door wall, 11' is tv wall).  TV can't be moved - this was a negotiation point for DH and I (I wanted it on the other facing 11' wall).

Clearly we have 2 standard doors to work around on one of the 19' walls and a slider on the other.  The 11' walls do not have encumbraces except for the tv. 

My thoughts right now are to do built ins around the tv.  But that's the one thing I'm sure about.  My big questions are:

1.  Should I do a l-shaped sectional or a standalone sofa bed?  If the latter, should I add a chair?  I would like to have comfortable seating for at least 4 people.

2.  How should I configure the play area behind the couch?  Do built ins w/ desk along that 11' wall too?  Would the room feel too enclosed with built ins on both sides?

3.  What type of window treatment for the slider?  Curtains?  Blinds?

4.  We have ZERO lighting in that room, so while we'll put overhead lighting or cans in at some point, focus around where to postion lamps.

HELP.  Pictures below

lindyanne

I don't have any specific advice but I have been using this room planner for our basement and found it to be really helpful at envisioning how things will actually lay out.