Sona is an outdated and thus flawed character design.
I'm not even going to point to her clear issues (mobility, low health, etc..). I would just like to address the fact that her kit is for all intents and purposes designed to function at 50%+ CDR..... Or with a metric ton of AP. Honestly play her in like 3 games and tell me she doesn't feel clunky and useless till you meet one of those two requirements. Yeah i get it everyone needs some built in weakness, that they can over come via whatever, but that weakness should not be fucking max CDR and/or 2 full built AP items on a support.
And what really gets me is i'm sure that Riot knows she needs to be updated to fit what the game has become, but "fixing" her is such a low priority. She feels like the metaphorical squeaky door hinge that you were going to deal with till the basement flooded, then the stove broke, then you had to deal with a insect infestation, etc... You want to fix the issue, but there is just so much more important stuff to deal with, and it's not like a squeaky door hinge is going to ruin your day.
I would also like to point out that her offensive support (non ultimate) "thing" is probably the least meaningful one in the game. To be more clear as to what i mean, imagine you got hit by Sona AA+Q+ empowered AA. Now how do you feel compared to when you get hit by ANY other 'supports' primary offensive ability; IE
's hook,
's bubble,
's root,
's polymorph,
knock up.
being a good example of a champ that needs to usually use 2 abilities for the one big impact thing). Even when you get something like
your power comes from being able to abuse the trigger multiple times rather then one shot with it.
actually helps her do more damage.
, but Thresh plays much like 
styles, while simultaneously reducing the risks associated with either.
This resulted in other supports having to be made more aggressive, after they were buffed in their old actual supportive designs, because those were considered unfun when taken to an equal degree of power as Thresh. But again, they set him as the standard from the popularity of the new audience playing the support role. Not the existing audience of the support role, and letting Thresh be the outlier.
2 years later
heals better with items, but she can still heal pretty decently by pumping points into the skill.
can really abuse
and that item line, but if he does trash damage until he gets it then you have an issue where he simply doesn't work right for a chunk of the game. Let's say i rush
level of damage output, i'm arguing that i really shouldn't be losing a trade with
or
. I'm arguing that a champion who's kit is based around casting a lot of low impact spells, instead of 1-2 big ones, should be able to cast a lot of spells without needing 40%+ CDR to keep pace.
has buffing but it sure isn't his freaking heal. No one is going to argue that
buff is it's healing instead of its bonus damage. honestly the only heal i would say is a buff is
and
/
/ or even older champions like