There is a Cake video where they demonstrate using single note MIDI clips in a do nothing MIDI track that represents song sections.
Basically you stretch the clips out to cover song sections. Selection becomes really easy - just click the clip or shift-click the clips and selection on the timeline happens automagically.
You could easily do the same with a single clip that covers all of the measures in your tune. Then a single click makes the selection.
I know it sounds fiddly, but it's really easy. I even added a 1-note clip to the root of my media tree. Now that it's made, I can drag it in and copy/paste stretch and have a whole song structure laid out in just a few seconds.
I'll update this post if I find the video again. Somebody else posted this tip in another thread ...