I've never had an issue with surgically adding, deleting, copying, moving, inserting blocks of songs, measures, parts of measures, repeats of choruses, repeats of verses, anything...
That's because I adopted using the Select By Time choice under the Edit menu early on and it's now second nature. Takes seconds on any decision or update.
If you need to add a chorus somewhere, for example, find where on the timeline you want the insert to occur. Figure out how much space you want to add, or just add wild extra, just not too little. Like say you need to add 4 measures. Then Control A (Select All) for the tracks.
1. Use Select By Time to select the range from where you want the insert to occur.
2. Cut Special to grab everything (including markers. (Control Shift X)
3. Paste Special to the starting point of where you want the cut portion repositioned (like 4 measures forward from where the cut occurred).
4. Now you have the 4 measure hole. You can use Select By Time to copy a 4 measure chunk and Paste Special into that spot.
It takes seconds.
It's surgical, way better than grabbing blobs or measures because there are many circumstances where you want to grab ranges that are very specific, down to beats or ticks.
Easy and fast. And convenient. Once you've done it a time or two you don't even think about it, you just move stuff around like Legos.