Poppys ult isn't as fun as it could be.
i wish poppys ult could work on immune targets like vi, Sion, malphite, etc. Poppies ult can't be considered broken considering it deals little damage, makes the target immune in the air meaning no cool or fun plays to be done while they are in the air.
Your never gonna charge your ult all the way and ult a malphite, it happens to fast, but you could press r and maybe save a teammate from their ult.
Just an idea to give poppy a bit more flavor to her ult. While it's a lot longer ranged than lee sin, it lacks a lot of the damage and cc which when a lee does it correctly can knock up a team and not make them immune to damage.
"GTFO of my Baron pit."