Here's something: Why didn't you update Sona's lore?
Sona's got a story, yes, but it's going absolutely nowhere. So she's Valoran's biggest popstar, but does that say anything about her goals? Does it make people relate to her? Does it contribute to the ongoing LoL story?
Not really.
IMO, Sona could use a better story. This remake would've been the perfect time for it. So what stopped you?