Anderton

Sanderxpander
You can also easily select the entire lane by clicking jn the top left of the lane header, then if you hover on the top part of the lane, you can drag increase/decrease the envelope along the entire length. Also useful for adjusting the overall volume of an already automated track.

This is one of my favorite automation shortcuts, I use it all the time.

As an added bonus, you don't even need to select first. If nothing is selected, it defaults to moving the entire envelope.

John T
...I think in X1 you could just grab an automation line and drag it up and down. Then in X2 and X3, clicking an automation line was changed to "add node" and you have to hold a modifier key to get the old drag behaviour.

Or hit F7 for "Move" tool instead of "Smart" tool.

Great suggestions.  I still don't want the last node, though. I find it more exact to right-click a node and change the value than to drag the whole envelope.  Sometimes 1db or 0.5db is the right change. Sometimes the mix sounds good, but everything needs to go up or down slightly to get the peak at the right place.  I find it hard to make those delicate changes by dragging, and it is easy to mess up the mix.
 
So, great tools suggested here, but I would still like Sonar only to add the nodes I want and not assume I want another at the end of the song.  This is a really minor thing, though.

FWIW, Konrad, I agree with you. I don't know why other folks on this thread don't seem to understand the problem.
 
I will mark your original post as "Helpful" because I didn't think of cutting the last node...

I don't work in the same way so I don't often run into the same issue you have, but I do agree with you. Every once in a while I'll have to mess with that last node. 

Cool, guys, thanks; and, again not the biggest issue in the world.