I've been doing projects like bashed locos, boatyards, etc., for so long I decided just to run trains this afternoon. I spent the morning cleaning up the layout and running track cleaning cars, etc., then set this up.
I have never run seven trains at once. All scale. My two upper loops are dogbones with reversing loops on both ends, so I can only run one train on each at a time, but I set up my five bashed five LC+ "scale" steamers with eight to ten car trains each on my number one mainline, spacing them around its 130 feet.
Uppermost (BEEPWorld) loop: MTH PS3 2-8-0 pulling shortened post-war rolling stock, running in conventional with cruise on.
Middle: Railking PS3 NW-2 cow and calf running in conventional.
Lower mainline. Five LC+ steamers, all the five I bashed into "scale" locos, running in remote mode. I set up the locos evenly around the loop, turned on all five remotes first, adjusted each to 1/4 throttle (3 PM) and then turned up the power. All five started up in unison, reached the exact same speed within a second or two, and cruised at the same speed, as you see.
It is fun but a lot of keep track of.