If it was me, i'd do away with the fiddle yard and make it into a scenic yard with a small satellite shed( yard power, locals), i'd add a dummy mainline at both ends to connect with the rest of the world, single track would do.
Then spread the industries out over the other two sides, with room for scenery, with a run round at the far end, spurs going both way, industry with 3-4 spots each, it's not the amount of industries, it's the number of spots it has that makes it interesting, have a look on google maps at industrial parks there's lots of industries that are not rail served.
At the end of the day it's your layout, so it's what you want, but to me less is more.
look at this https://thehillsline.com/ http://www.iaisrailfans.org/gallery/MJMGrimesLine