Ok I'm working on my yard design for my new layout. I'm modeling a transition era so I'm running both Steam and diesel. I've got a couple of design's I'm working with and have a few questions. I have a turntable and roundhouse that will be a main focal point. 

Here are my two designs and looking for some input.

My first design is your typical roundhouse and turntable with the engine servicing facilities layed out on the side/entrance to them. Here are the water tower, coaling tower, diesel refueling, washing area etc. The main line track will run in front of the roundhouse near the front edge of the benchwork.

My second design/thoughts is this. Move the roundhouse/turntable out to the benchwork edge. Run the mainline behind the roundhouse. But with this design, I don't have enough room to put in the servicing facilities. So I'm wondering how important it is to model them? Can I just put in a few items? Or just paint them in on the back drop? One advantage of this design is that I can do a cut away of the roundhouse along the edge so that you can see inside of it which adds more detailing to the model.

I guess this is more a function of operations. In that when operating, do you account for time to service the loco's? Do you actually park them at the fuel/water and sit for the amount of time it would take to service them? Or is it just kind of a given? I'm not sure how much actual true "operating sessions" I'll be doing.

I know it will make the layout look better to have all of the structures but just wondering about this. Or I may be able to put in Half structures on the back drop. My biggest problem with the whole section is that it's on a curve.