Sona 6.13 Changes
I've always known that Sona needed to be balanced around late game. So these most recent changes aren't that much of a shock.
Sona will REALLY need to hit level 16 in most games she plays for this change to be neutral and not just a total nerf. I'm not sure the XP for dying without an assist will really help her, since getting an assist with Sona is brain dead easy AND her auras are getting bigger.
If games are ending with both supports at level 14, these changes are going to be a huge nerf. More importantly....
If Sona is losing her heal scaling AND losing a chunk of base healing, lower the damn mana cost on W. It becomes almost mandatory to spam it now instead of using it in a clutch situation, so it doesn't need to cost 100+ mana per cast.
Q changes look fine, though I will echo what the PBE said the first time around- if all my skills have a 10 second CD at level 1 it's going to make for a VERY passive land phase.