I live in north Texas and it is flat as can be here. I personally hate where I live if I was to model it because the idea of the flat Texas planes. I would like to model the Rio Grande Railway after I finish my first layout and I might be able to find some space to place the layout. Anyways, how many other people would hate to model the railroad in the are that you live in?
First of all, the "scene" in which you set YOUR rr, is limited only by your imagination...like I said, it's
YOUR rr, & your world!
That said, I think a lot of us gravitate toward what we are familiar with...where we live, where we grew up, childhood memories, oh...& did I forget to mention...Our favorite railroads!
There's beauty in all geography though, IMHO...I live in KY, so I tend mainly to model coal country...rolling woodlands, & Appalachian scenery...
But even in flat country, there are interesting scenic elements to be modeled both above & below track level...streams/washes, grade crossings, structures...just because you don't have an abundance of trees & hills doesn't mean there's not a lot of visual interest, & therefore modeling inspiration!
But hey, if you prefer, there are plenty of photos out there of the Rio Grande cuttin' through the Rockies! If that's what gets your juices flowin', go for it! Do it your way! That's the beauty of this hobby, you can go anywhere you want with it!