You'll probably hate this idea, but...
It all comes down to whether you're a scratch-builder or a buy-it-and-stick-it builder, and I mean no criticism in that description. Anyway, there seems to be a knee-jerk tendency to build industrial layouts for HO, probably because there is so much available to buy off the shelf and it's size, admittedly, works well for that.
My suggestion is totally different...have your layout centered around a resort-city. You have the room for a racetrack, horse paddock and barns, hotels, casino, a lake, and a small town to service the customers---banks, gift and souvenir shops, spas....swimming pool at the hotel with people on chaise lounges around the pool, expansive lawns with statuary, neatly-manicured trees and bushes...perhaps even a celebrity cemetery, a la' Forest Lawn. I like different, and I just can't get excited over another factory-town layout. (No offense to those who have one, but too many people followed in your footsteps and now everyone in HO has a factory town!).
Thus spoke Reckers.