I use the Atlas program, and was happy with the results. It has all the Atlas track as part of the program, which is why I went with it. It made it super easy to come up with a plan, and at the end it gives you shopping list of what you need. Not sure I'd recommend it if you are using another brand of track though.
The first time I did a layout I used the Atlas program to draw the track plan even though I was using Peco track and turnouts. I had to make some adjustments when I was putting everything in place but it was fine for what I was doing. I don't think it works on a Mac though.
XtrkCAD runs on Macs too, but may have to use Apple's built-in x86 emulation to run on the newer ARM processor-equipped Macs. Same thing with Windows on ARM.
