Sona either needs a rework or just play her super passively
Sona's really outscaled by every support. Honestly, every champion Sona counters beats her now. She also doesn't have very reliable CC. Yeah she's got an auto target poke, but it doesn't do as much as other support's pokes. Plus, if you try to auto, you'll get engaged on, and possibly die (which I've seen happen frequently). She's got a very weak heal and shield, which makes me feel like Ahri can heal more than her if she uses her Q heal on one minion. Sona's E is meh, still kinda useful. Her ult is also fine. Her aura concept is unique to her, as well as her empowered autos, which I like. I just feel that her Q and W need reworks. The only time I see a Sona win is if her team carries her.
Maybe her Q could become a skillshot that goes through champs and minions, but keep the aura so that allies can get the empowered auto attack. If she autos, it will do bonus damage and apply grievous wounds for 1 sec (or whatever fits best). For her W, she can make an aoe heal in some shape and size in front of her, and her aura will still shield (hopefully the heal is for a greater amount). If she autos, they are silenced. I'm making them like this because auto targeted effects are often weaker than skillshots. Take Brand for example. His E is definitely weaker than his W.
I love Sona because she's a beautiful champ, but she's one I avoid now because every other support can beat her. Really hoping that she'll be improved.