small HO scale layout

hi everyone i tend to post alot of layout threads that lead nowhere but i have now switched back to ho scale and would like help designing a 4x8 or 4x6 layout with a 6x2 extenion (only if 4x6) so its a manageable layout.
some of the criteria i would like are:
- continuous run
- change in grade
- small yard that doubles as an interchange
- use of magnetic uncouplers
- all peco code 100 track
- engine shed (2 stall) but no turntable

i am finding it very hard to decide on a track plan so all help will be much appreciated

 

Model Railroader's latest project "The Virginian" sounds like a pretty close match to you wants.
It's 4'x8' with extensions.
The project will be in MR Jan.-May 2012, and there are a bunch of videos on their website as well.

 

Thanks i like the layout except the yard area ... might play with the plan in xtrckad later