Thing is on my layout I don't have a mainline per-se. The Main exists somewhere off layout. I do have a set of Inbound/Outbound tracks that sit next to the yard and are connected to it by a set of curved t.o.'s (single x-over) at the corner of the layout. The IB/OB tracks also make use of the double x-over I hand laid which sits at the end of the layout about a foot and a half from the edge. I was thinking about putting a tower next to the double x-over, as a means to "control" traffic coming on to the layout from the Main.
From the stand point of me operating the layout I want to put it in the corner of the layout where curved t.o.'s are. Mainly due to the fact that so far when tooling around after working on the layout, I spend most of my time primarily at that end of the yard working the trains. Switching the t.o.'s to divert onto the industrial trackwork from the lead.
I also recently wired up and installed 11 tortoise machines (3 more to go for this batch) for which the control boards sit mostly in that corner. So I feel like I am controlling everything from that point on the layout.
Eventually I'll have switch machines installed at the East ladder end closest to the double x-over, however that is besides the point for now.
Does that make any sense at all?