Why does Ekko MID only have Electrocute as the best option?

Hello everyone

I've been a fan of Ekko MID since its release ( PS: It was made for MID, but Riot threw it to JG) But I always noticed the lack of other runes for our boy. This year we had First Strike and it was so nice to have two rune options for Ekko that you could vary your gameplay, but Riot nerfed the rune.
Fleet Footwork sometimes I see some main Ekko using it in some matchups, but it seems that there is always something missing in terms of damage with this rune.The lack of synergy with the Precision Tree tilts me sometimes There is Hail Of Blade that I also see some Ekko use in some matchups but even so this rune is way below Electrocute. In my opinion it sucks to see Sylas, Diana, Kassadin, Akali, Katarina and others have the option to turn the rune and still be quite effective.