You are absolutely Fine!

Its a good thing that her numbers are dropping that is what you want to happen! :thumbup The goal here is to get Eleanor down to staying between 50-120 as much of the time as possible so that her pancreas can heal and take back over making her own insulin.
The only time you have to worry is when you start seeing numbers in the 30-50 range very early in the cycle at like +2 or +3, otherwise she is doing what she is suppose to do, coming down to that normal range again. I have 13 cats here only 2 of which are diabetic, all my non-diabetics (yes, I test them too) run between 45-50 and even my one diabetic that is now diet controlled runs about the 60s all day everyday. The whole idea of giving insulin is to get those preshot numbers to drop down into a nearly normal range, and stay there as long as possible.
My Musette and Lillian's Kitten both don't really do curves most days, they do slants. In Kitten's case he has a late nadir and with Musette it is because that is her pattern. Every Cat is Different and through testing we all learn what our particular cat's pattern is. Some run higher during the day, some run higher at night, so have a flat curve, some have a steep one early on or dive late. None of this is out of the normal for that cat, in fact I have noticed that while Maxwell is OTJ now for over a year he still follows the same pattern he did when he was on insulin...If I spot check him in the morning he will be lower than if I check him during the evening hours that is just him, Musette goes the other way, she is always higher in the morning and lower in the evenings.
Mel, Maxwell, Musette & The Fur Gang