I do wish Riot would be tackling Sona/Karma/Lulu/Nami first
I almost never have a reason to pick one of them over another. Only exception I can think of is choosing Lulu/Karma against Leona/Blitz because they are better at surviving burst/all-ins. Or if I'm early roaming more I'll go Nami/Karma. That's really it.
They all bring very similar things to their team and also play very similarly too (poke early and then be a utility bot later).
People complain about Soraka or Janna but at least they are uniquely amazing at the one thing they should be doing (healing and peel respectively). Only reason to pick the others is because they are general all-around utility bots with no clear purpose other than to just exist and be useful. Karma especially fits that description so much it hurts.
And yeah, I like bringing this up. =S
**EDIT: **I would personally:
Lulu: Buff her ult but remove the option to use it on herself. Possibly make her the "I'll make anyone a tank" pick. Make the ally effect on W contribute to that as well.
Nami: Give her powerful bonuses in the river. Make her the queen at contesting Dragon or Baron. But maybe overall a bit weaker outside of that.
Sona: Buff her E to ridiculous levels so that she's the 'movement speed' support. Remove the AP scaling but increase the base values to ludicrous levels. Tweak the other aspects of her kit as necessary.
Karma: I honestly would have no idea what the f*** to do with her at this point. And Karma players seem to love complaining about any changes made to her anyway. She's a fun, balanced champ but has zero identity. And people still can't even figure out what lane she's best in or should be in. Which would be a cool thing about her if she was unique... but it's not. Her contribution to her team is summed up by "She's useful to have around I suppose" as one guy said to me once.
Perhaps give Karma an entirely new niche such as buffing her team's damage output as well as contributing with her own (After all her name is Karma, which would indicate inflicting pain on others in some kind). Enemies hit by Q take increased damage from allies. When broken by an enemy champion, Karma's shield now provides a buff that increases damage dealt. Enemies rooted by Karma converts 20% of all damage received by allies (not Karma herself) to true damage. Things like that.
(Don't take these ideas overly serious -- they're just ideas after-all)
@Meddler or Repertoir will these champions be looked at, at any point?