Athene's: Shields + sustain = wisdom?

Was it wise to give sustain to shield lanes? shouldn't healing vs shielding be a strategic choice, especially with GW reversion?

Shields are proactive, better in combat / trading: they can't be reduced, are effective vs burst dmg / assassination (pre-emptive shielding) , increased defences from windspeakers always increase effective shield value even more). downside: if you manage to play around them the damage is going to stick.

heals are reactive, less effective in combat / trading: can be reduced (GW), prone to burst (can't pre-heal someone that gets assassinated insanely fast), resistances from windspeakers are missing during the initial fight (no dmg = no heal = no resistances) and have no use for out of combat sustain. Upside: allows you to recuperate any damage taken during the trade afterwards.

Athene's essentially removes the only downside shield champions have compared to healers. even if you manage to play around / burst through the shield the damage is'nt going to stick anymore. healers on the other hand get bigger heals but they still suffer from the same weaknesses. shouldn't it either simply enhance the current strength's and weaknesses of shields and heals respectively? i.e. shields use bloodcharges to increase shield value, heals to increase heal value. or if it's intended to counter the weakness shouldn't heals use bloodcharges to shield?

Karma + athene's almost turns into a skilshot sona, and do lulu and and janna really have to be able to sustain / counter poke in addition to their already superior ability to cockblock all-in attempts.