North Californian Layout

Hi everyone,
Many thanks for all the insight and info. Would it be feasible if I were to build a U shape layout with one side of the U modelling the central area of Ca. and then linking it to the other side of the U through a hill range to model the coastal line of Ca. I want to corporate the following industries ( as I already have these ) into my layout. 1. grain silo; 2 lumber mill ; 3 oil/fuel depot; 4. foundry building; 5.tool factory 6; meat works and 7; two wharehouse buildings. My railroad will be a freelance railroad named “Helendale Valley”, but at the same time I want it to look like it is part of California. Most of my diesel locomotives are either UP or SF, though I have thought of painting them to my own railroad livery. Do you think that as a new modeller I am biting off more than I can chew? Any advice gladly accepted.