What if instead of circular auras, Sona instead used conic skillshots that would radiate outwards

Because she already has a failed design. Her secondary actives(the bubbles) already have an absurdly small radius, 100 units smaller than any other support spell in the entire game. Changing the primary actives in cones first A) makes the weakest heal in the game even weaker, B) Rito would sooner nerf Hymn's damage than buff it, especially if it became AoE, despite already being the weakest damage support spell in the entire game and C) her already useless MS spell would just be even more useless than it already is.

The only spell that should become a cone is Crescendo and ONLY if this means it gets increased width and range to the shit-poor hitbox it's been shadow nerfed to right now.

No, we don't need even shittier designs than Sona already has, we need her to be reverted to pre-4.13