I've done a few (as you know), and you're welcome to them. The first 3 are all N scale.
A 4x8 in N scale is much more "doable" then larger scales. I'm not saying you can't do a larger scale in this space, but the size limitations make themelves more and more obvious as the scale size increases.
And you're right, all 4x8's have cons, even (or maybe especially) mine.
This is not a bad plan. It's one of the better ones I think I've done for this space. I don't know why I gave it western scenery. It actually could be anywhere. I like the way the yard flows, though it could be bigger. There are a few customers on the line, so thats good. There's no staging, so that really hurts the design, but there is a place for expansion in the lower right. Minimum curve radius is 15" and the smallest turnouts are #5's.
http://i83.photobucket.com/albums/j319/pcarrell/Track Plans/4X8NSCALEOLDWEST.jpg
This one was done for someone who wanted big diesel action in a small space. Most of the track appears to be double track, though it's really single track with long sidings. The bottleneck in the top center keeps operaters on their toes if they're running two trains. the yard is not too bad, though I'd probably add a turnout to the A/D track to allow travel in both directions. Thats probably the weakest point of the layout. The partial scenic divider allows for a larger "feel" to the layout, and thats probably it's best point. Minimum curve is 13.75 and the plan calls for no smaller then a #5 turnout.
http://i83.photobucket.com/albums/j319/pcarrell/Track Plans/Rob1Nscale.jpg
And here's one I never quite finished up, but I think you can see where I was going with it. It has a pretty healthy grade on the branch and the staging, but if one goes up while the other goes down it isn't too bad. It definately has the roundy-round thing going on, but staging helps operations a bunch. You just have to be able to get to it easy enough to make it worthwhile. Minimum curve radius is 12.50" and the smallest turnouts are #5's.
http://i83.photobucket.com/albums/j319/pcarrell/Track Plans/4x8Nscale-7.jpg
Just for giggles, here's an HO scale plan I did for someone. It lacks a way of turning loco's (not absolutely necessary), and it has no staging (biggest fault of the layout), or even a place to expand from. It also has all of the track parallel to the tables edge - a big drawback visually in my book, but thats what the customer wanted. Some of those issues could easily be addressed though, while others would be more difficult. The person I did this layout for wanted to mostly railfan and occasionally switch cars. This layout does that. Woodsy and slightly mountainous, with a business in the valley feel to it, it's not too bad scenically. A better scenic treatment for this one if you ask me would probably be in a rather grungy urban setting, with lots of multi story old buildings and a few vacant lots - your basic concrete jungle. Minimum curve radius is 15" and the smallest turnouts are #4's.
http://i83.photobucket.com/albums/j319/pcarrell/Track Plans/Alexs4x8Revised.jpg
