Created attachment 158948 [details]
1.png

As you can see in attached screenshot, a lot of space is lost probably after this commit:
http://git.gnome.org/browse/evolution/commit/?id=ce11d292c5487743d0543dd998cfd26b8afd0827

Even if old padding could cause some people to feel it like too packed, it saved much more space and I think it was much better than current one. 

Maybe the best option could be to allow people to set padding as they prefer but, since maybe it could be difficult to implement, why not set default value to a lower one than "4"?

I think that you could use as reference padding between lines used in the header of messages (I refer to the one used in "From, To, Subject..." in mail view)

Thanks