There have been a few discussions about selecting regions or sections in projects and having a structure map of sorts visible.  I can't remember who first posted this link, but I finally found it again.  Thanks whoever you are!  :)
 
From ~1:02:40 thru 1:05:10 Seth describes this little trick he came up with

I miss those webinars.

I started watching, but it is X1. I started really using Sonar with Platinum. All the other upgrades since Dos have sat on my computer with little use, due to lack of time and knowledge to dig in. I am retired now, and with the help of training videos from here and Groove 3, I am getting the hang of it. I am afraid of confusing myself with the older version. Thanks for doing this, I am sure there are plenty of guys who will appreciate the effort.

The part of the video I referenced works in all versions.

Not only do I have a "lane" for markers, but I also have one for chords!
 
I do this so it is easy to play along with - I can see the chords scroll by.  

This is just my starting template.   No, my entire song is not G# lol.
 

 I have wanted to have something like this for a long time as the markers themselves are not always easy to see.
 
Thank you for posting! like the chord idea also.

Can you make cross track selections groups that incorporate everything in a time range?
Just click this top clip - and everything through project track range can be selected too, in one go.
 
Maybe with one such selection you can insert time as well, to make room.
 
I have to try that next time at Sonar daw.
It would really be a neat start of arranger track stuff like many of us has voted for.

The only thing that bothered about this approach is the fact that MIDI tracks can't have a real NONE as their input.  I've been archiving these guide tracks, but that dims the colors.
 
Quite by accident I just "discovered" that I can put these MIDI clips into an audio track-that really can have no input or output.  No need to archive or even change the velocity of the note unless the line bothers you.
 

BobF
The only thing that bothered about this approach is the fact that MIDI tracks can't have a real NONE as their input.  I've been archiving these guide tracks, but that dims the colors.
 
Quite by accident I just "discovered" that I can put these MIDI clips into an audio track-that really can have no input or output.  No need to archive or even change the velocity of the note unless the line bothers you.
 

i have these tracks running through an empty drum map, so this way it doesn't trigger anything.

I've been using these color markers for several years. Prob saw it on that video...
I used to have to 'mute' this color track to not have it sound.
 
What I do now is put 1 midi note in the clip, then drop the volume down to zero. As I copy/paste that clip for different sections of the song, I'll change the background/foreground colors via the inspector. Never have to mute again.
 
Chord track! Love it and will incorporate  in the future. Just too hard to see chord symbols as a name for a marker.
 
Michael