Possibly, but I think you are heading down the right path.
If you know the old system was flawed, and this redesign is making sense, then stick with it.
Most developers on here will tell you it's far better to start again, than "adjust" an existing system if it wasn't working.
But if you need to store your data a bit differently and or introduce some changes now is the time to strike, and it's the best time to make those "improvements" as necessary change.
Obviously your working reports etc, are fine, and can be tweaked if new data is required.
From your earlier description, it sounded as if the AFR numbers were possibly being reused ? That sounds a bit dangerous from a data perspective?