I've just played with the Zyra changes on the PBE and my goodness, they feel amazing. The AI changes are a joy to use. But have you considered that she may be too good after these buffs? Would some compensation nerfs not be in order?

Yes, we did a small bug fix yesterday in response to the PBE feedback about Q plants being extra sneaky and just sniping champions at long range regardless of circumstance. We've fixed this but kept the fluidity of attacks, derp fixes, and other adjustments.
We agree that the AI changes were more power than we wanted to add (pretty easy to do since plants are the vast majority of her damage), and as such reverted the knockup increase. This will let us get a good sense on the Live environment how much impact the AI changes alone will do and inform us of future work.
I much prefer scaling down a buff if we feel it'll be overkill than putting in compensation nerfs if we can avoid it.