Not too thrilled by the PBE Sona changes

The raw damage on her Q and the healing on her W is nerfed at max level (but a little stronger earlier). Her ally based stuff (invisible power) is getting a slight buff. The weirdest thing is as she levels her ult, she is going to get more spammy. This spamminess is a concern. Sure she is getting more spells, but they are individually weaker *for her at max level. One of her problems is she's got a lot of invisible power so riot seems to be nerfing her directly, giving her more invisible power, and then letting her spam weaker spells.

Here's my problem with this. Right now sona seems to be in a pretty good spot. She's got a good winrate. Nami and trundle heal more than she does. Other supports do more damage and get more kills than she does. She's not heavily picked or banned. I don't think she's pick/ban at the pro level. So why is she getting these weird changes aimed at her late game?

I think the worst thing about this is because despite her squishiness and her weird mobility, Sona is one of the few supports who has a bit of carry potential and doesn't completely need her teammates as heavily as the other ones do. Now riot seems to be trying to take that away from her. As someone who's been forced to take Sona into a solo lane on too many occasions before because my teammates didn't tell me they were doing weird things like double jungle until after I picked her, this kind of scares me. As someone who knows sometimes your ADC is going to be having an off and needs someone who can both babysit and help make plays, this kind of scares me.

Yes sona has always had invisible power in her kit, riot has always hated that, and now they seem intent on reversing that course. The timing of this strange inconsistency is the oddest thing of all. Some context on why these changes are happening would be nice.

Nerf info listed at Surrender@20