Dennis,
That helps a LOT! Thanks for clarifying.
I guess I like the basic concept since it is pretty close to my own; yours is just stretched a bit more. Running two trains, one at a time, I typically get almost 3 hours of operation in. The green line on the layout gives me continuous running. During an ops session, I use that track only as an imaginary interchange point. (The drawing is a bit out of date but will give you a general idea.)

And, for comparison, your plan.

Now, a lot of what I say will be very much based on my personal preference, so of course ignore the stuff you don’t like. 
Your layout has the appearance of a double track mainline. I know it isn’t, but it sure looks like it. For narrow gauge, I prefer the look of a single track going through the terrain.
If you’re going to do any operations, you will need a lot more spurs. Right now it appears that the only spur is on the trolley line. (Unless that’s NOT the trolley line; but either way you need a lot more spurs).
That’s a BIG yard and it will be very hard to reach all the way across. In fact, I don’t think you’ll be able to reach all of the tracks unless you go to the other side of the peninsula. Plus, without any spurs, you have no real reason to have all those tracks. I only have 5 tracks in my yard; it’s tight but challenging.
I forgot to ask - will this be elevated or on the ground? If elevated, you want to make sure that you can follow the train without having to back track around peninsulas. It could get awkward switching that large yard if you have to keep going back and forth to either side.
Instead of a double ended yard, I would prefer a turntable at that end of the layout. You can still have continuous running, of course. But, this gives you a change of direction at that end as well as an interesting feature on your layout.
I think most of your track is way too straight. I prefer gentle curves as it seems more visually appealing.
Even if you don’t plan on operating more than one train at a time, I like the idea of including a couple of passing sidings. I use part of the siding for LCL industry, so I end up moving cars out of the way when I run a train. Makes it operationally interesting.
I don’t have a trolley on my layout, but if I did, I don’t think I’d connect it to the mainline. The only reason that I might share the main would be if I was to have its operation automated so it just went back and forth, and I had to run my train with that in mind. If so, a gauntlet track might be very cool.
I like a place to “stage” trains. My top left loop has a siding where I can hold a train already made up, so it’s ready to go without any switching; this represents the off layout portion of my railroad and allows me to start a train in the opposite direction. If I wanted to, I could run two trains at once and have them meet somewhere there’s a passing siding, though typically I do not operate that way.
Well, I hope this gives you some ideas. The key thing in this is to build the layout that you want. All of us have our own opinions about what makes a great layout, but it’s only our way; not yours.