+1
I've asked for this a number of times too. I even made a point of it when we were asked to provide feedback in that survey a while back. I was thinking along the same lines as the OP - with a capability that looks like automation lanes, where you can add, move, or drag nodes. Once in a while I would have liked to just grab an entire "automation line" and move it up or down globally to speed up or slow down the entire song, all while keeping relative tempo changes intact. Yes, better tempo editing would be a definite plus!
 

So we've had a year of rolling updates and they still haven't rolled this into it?

+1 for Tempo View update.
+1 for Tempo Lane. It should be not too difficult to reuse existing automation lane codebase for Tempo Lane.
 

Yep. There have been many, many threads about updating tempo/timeline, especially if you consider other timeline-related stuff in that category - bar 1 offset, tempo regions. 
 

Something like an automation line you can blend in, like the thing in ProTools. Looks similar to the new controĺlers in the new PRV since platinum.

+1 on Tempo View upgrade.
 

and full CC automation of Tempo

+1
+1

I'd also like to have the tempo map be "smart" when you move (cut and paste) sections of I the track view that involve tempo changes.

When you cut a section, I think the tempo map should insert a redundant tempo change event just before and just after the cut on both boundaries, so that individual clips don't jump around unexpectedly. Currently I have to do this manually and it's a real pain.

Too bad Sonar doesn't have a warping feature so audio clips would follow those tempo curves after we get this feature. Need to make a FR for this...

My usual bump for this, since it still doesn't appear to be on horizon of the developers.