I wouldn't put any more structures on it. It looks fine as it is.
I built my RR by painting the track and then ballasting before ground cover. When you put down ground cover some will intermingle with the ballast which happens in 1:1 railroading too. If tracks are being newly laid in real RRs, the ballast goes down before the grass and weeds take over. It the track is being re-ballasted, the ballast goes over top of the grass. So either way is prototypical. I chose to ballast first because I didn't want to be leaning over and putting my hands down on landscaped areas. Take particular care to keep ballast out of the operating parts of switches.
I did some remodeling of the track recently and ballasted AFTER ground cover was there. That worked too, but it made the ballast look very new and fresh. Whatever you do, if you're airbrushing the rust color for the track, make sure you do it before ballasting. The air blast from the air brush will quickly blow away the ballast. No good.