Can we Rework Sona into something better?

TL:DR at bottom

Sona in her current state is "weird" in so many different ways. If you look at her numbers you have an auto target ability that 80-320 magic damage with 120% AP ratio, can give her allies 50-150 bonus magic damage (with 150% AP ratio), you have a heal for 60-220 health with a 50% AP ratio, a shield that can block 125 damage at rank one and up 625 damage at rank 5 on top of maxing out at 150% AP ratio, you have a movement ability that can give a total of 50-70% movement speed to your allies for 3 seconds PLUS 20% AP ratio. To top it all off her ultimate gives her a flat 10/25/40% CDR to her basic spells. On paper this champion would be broken beyond belief.

But once you start breaking down how those numbers work it becomes a whole lot less impressive. That 80-320 magic damage spell with 120% AP ratio, well that can ONLY hit 2 targets and they both will be taking half the damage. So you are only doing 40-160 damage per cast. The bonus magic damage is only 10-30 per ally tagged with a 30% ratio for each. This means that trying to solo lane with Sona is insanely hard since you lack wave clear and your damage output is halved what it would be in a duo lane. Something else to keep in mind is that your single offensive spell is on a 8 second base cooldown. So not only are you doing unimpressive damage but you are also doing HORRIBLE DPS. Her heal is also split between two units meaning that you only heal for 30-110 heal with a 25% ratio for each. This means that you have a negative cost to healing ratio at rank 1, and besides that you won't be saving your ally with a clutch heal during a fight. Her shield can effect herself and all her allies but that means that at rank one it's only preventing 25 damage per ally and has a 30% AP ratio. This ability is on a 10 second cooldown, meaning that you often will get to use it once per fight in the early game. And i think most people will agree that negating 55 damage isn't enough to keep an ally alive if they are being chased. So now we get to her movement speed ability. +50-70% MS (with 20% AP ratio) for 3 seconds sounds AMAZING, but 10-14% with 4% scaling sounds a whole lot less impressive. Finally we get to her ultimate, this is the first instance of Sona having a stun and i will admit it is a stun capable of possibly hitting all 5 enemies, that said it will usually only hit 1-2. Now the passive on this ultimate is kind of weird, mostly in the fact that it was added because Riot admitted that Sona simply didn't do enough in the late game with the traditional 40-45% CDR. Your numbers were just to low and your cooldowns too high to function once everyone was running around with max abilities and a full item kit.

Another thing to factor in when talking about how good or bad Sona is, is what items she "breaks" and how. It's not uncommon for some champions to be abnormally good with certain items. Someone like breaks several on-hit items simply because his primary damage source, a long range poke, will trigger their effect letting him output very high damage from relative safety. Sona is no exception to this certain support items are down right "broken" when you use Sona. Take for example any of the items that give bonus heal/shield amount. Where most champions can only get a 1-2 bonuses from the item, Sona's ability can get up to 7 instances of the bonus. We can also look at specific things like Sona's interaction with where for a support like this item would give an 8% bonus to her heal and give a single unit 10-30% bonus AS and 5-20 magic damage on their autos for 6 seconds, on Sona this item can give a WHOOPING 56% bonus to her heal/shields and up to 50-150% bonus AS and 25-100 magic damage on auto attacks. is another example of an item that pairs abnormally well with Sona. Your offensive spell auto targets meaning that you can reliably charge the hell out of this item, on top of that since you can shield multiple allies with a single ability it is very possible to trigger a heal on multiple allies with a single cast of your W.

My suggestion to dealing this these issues is to rework Sona. I'm thinking something like a focus on single ally buffs instead of current team wide version. You increase the amount the buff does, lets say double it. So her bonus damage is now 20-60 magic damage (with 60% AP ratio) on next auto, your shield is blocking 50-250 damage with a 60% ratio. BUT these abilities only effect Sona and one other ally. This change removes Sona's "best case" numbers, which frankly are insanely high, and normalizes her with slightly higher base numbers. It also greatly reduces how much power she gets from a heal/shield bonus item, which means more power budget can be spent on aspects of her kit. Too top this all off i also think that Sona would greatly benefit from having a 25% reduction to her base cooldowns. This change would help Sona be able to do more during the laning phase, be it help keep any ally alive, soften up and enemy so your lane partner can get a kill despite your lack of engage tools, or get a kill against an enemy that is near death.

TL:DR: Sona would greatly benefit from a rework that pushes her more towards single target buffing instead of team wide buffs. I suggest doubling the base numbers on her buffs but limiting them to a single ally buffed. Reducing the base cooldowns of her abilities by 25%, but removing her ultimate passive. It opens up a lot of power budget by removing the "best case scenario" limiter she currently has to deal with.

P.S. I think it could also be interesting to see Sona with longer base cooldowns but her aura's last a little longer and give bonuses so long as allies remain within. A little bit of her old version and a little bit of her current version.