After spending years keeping up on model railroading I'm ready to take the plunge and do a layout again. I'll most likely go back to HO (though my stepfather's interest in O may inspire me yet.) I want to do a free lance layout based in central Illinois leaning to NS or CNW. I really just like the fell of rural Illinois and wanted to replicate it. Oh yea, I love grain elevators too. I have about a 15 X 20 room in my basement that can be finisihed with minimal work. I am pretty much settled on a twisted U shaped layout with 22" shelves and is fully walkaround with decent room for staging. By the looks of it this design will allow for about 90' of mainline. I know it is not alot but is it enough? I would like to keep a couple of operators busy following their trains but don't want the trip to be too short. I could stretch the layout to 105' but it would include a few duckunders and lots of curves. The cieling is too low for a mushroom and a double deck is out of the question. So what should I do? Go with 90' and have a short (but hopefully ample) mainline? Should I make it more of a long branch line? Is looping the layout back around a good idea? Thanks for the help.