Eric: I tend to be in your kind of school of thought, I love trains running, I love scenes for example where a moving train moves through a yard-like area where there are other trains/cars 'parked', head to head passing on adjacent tracks and so forth. I agree that operations makes running a train more fun, and I understand how the design around operations philosophy can make for an interesting experience over 'loop running', and I would encourage someone to have a layout where you can do operations, things like switching around yard areas, making up trains, etc, having industries and customers that require being served, but looking at your plan I see a lot of places to do that. When I actually figure out RR track software, which at present seems to be my bete noire, I for example love industrial and wharf scenes, with small engines switching them, and will try to have that as part of my layout, but the nice part about any layout is it can be an expression of anything we want it to be.
It might be easier with less track to have more scenic elements as Eliot recommended, the kind of elements you mentioned might be difficult with this much track on the board, mountains and hills tend to take more space than people think, and even having room for mundane things like streets, depressions/gulleys next to the track, other elements do take some space. I seem to recall from John Armstrong's writing on track planning that it always comes down to deciding what we want, what we need and from there it comes down to compromises. If ultimately having a lot of 'track action' is what drives you, then you can compromise on the scenery.
One thing I noticed was the track in many places seems to be really close to the edge of the table which I suspect is caused by a plan with so much track density. You may want to rethink that, by having space between the track and the table edge you can put in scenic design elements there, you can have things like old ties, signal boxes, paths, roads, etc there, visually it can look a lot better. The other trick might to be to try and find a way to make the track not as parallel to the edge of the table as it is. Thalt may be more difficult, but is something to think about since you are only in the design stage
You asked about the trolley loop, if you don't already have three rail equipment, have you thought about maybe using 2 rail equipment? Since the Trolley loop is not contiguous with the three rail layout, you have that option. The only reason being it is a lot easier to blend the track in with a street with two rail. If doing three rail, city streets is relatively easy, or you could use wood forms between the rails and outside the rails covered with joint compound that has been painted to simulate concrete. Key thing there is keeping just enough space to allow for the flanges and also to make sure the road surface is a hair below the top level of the rail, especially around the third rail.
Nice thing about this is a layout is not set in stone, we can always modify it, add/take from it, tweak it, or even take it down and start from scratch (some people, like Pelle Solberg over at Model Railroader magazine, seem to love building layouts then tearing them down and starting from scratch more than running them. Even with design software like RR track and SCARM, that can show us so much of what the layout will look like, in the end experience seems to be the best teacher from my years of being an armchair modeler, that you find what you like/want/need more as time goes on and the layout can be done to suit those unfolding desires (sorry for the philosophical bent to this, but sometimes it seems like people focus on getting it perfect 'right off the bat', when what is 'perfect' isn't set in stone