And can someone explain to me what's changed about Sona's "identity?"
For me a big part of what drew me to Sona was the idea of the music being the power she had. when i pressed QWE i did not see it as "casting a spell" but instead changing my song the music aiding my allies in battle Q invigorating my allies to strike harder, W re-enforcing my allies resolve to stand in danger and endure hardships, and E a song of high tempo and joy to fill my allies with fast feet. those effects were small and constant as the music that gave them there power was constant, with the change to give her auras bigger, but shorter duration effects fundamentally change that, the power comes no longer from the music she plays, but from barely the first note she strums.
listening to magical music gives you a shield that last barely 2 seconds, a single augmented attack, or a one time speed buff, it just doesn't make sense, the first seconds of a song are not the part of songs that make me feel all the emotions and sensations music in the real world gives you.
And furthermore to hear that magical music you don't need to be standing within a few persons lengths of the player, or dose Sona just play very quietly? and we have to get very close to hear her.
Music is made of both rhythms and crescendos, with these changes the rhythm is gone there's no longer a need to chose an aura, to play the one song that will benefit your team the most for the situation, because in a split second you can hit all 3 buttons and give your closest allies all you can give them in an instant, and then the music stops, and there is nothing but silence until her cooldowns come back up and the music is allowed to begin again
For context Sona was my first champion i chose to play, and the champion i "learned" to play league with i did not play ranked in S2 and i considered her my main though out all of season 3. weather or not this is good for her playability i make no comment, but her identity has changed, and perhaps for the few of us soft hatred that fell in love with that identity we will just have to be disappointed.
sorry that got longer than i thought it would.
TL:DR pre change Sona was all about playing music to give consistent small buffs, post change its about strumming a short chord for a short buff, where she once personified the identity of music its peaks and its valleys, its crescendos along with its rhythms, now the identity of music has been muted down to nothing but short crescendos and pauses.