It would be helpful to have a comment-type fields for data points, explaining their reason to be, why the settings are what they are, etc., so the next unfortunate soul to come across this would understand why such a point was created, etc. And as my college professor would often remind me, in the context of commenting, in a few short months I qualify as that new unfortunate soul with no context to understand why it was done that way.
Additionally, changing the multiplier and additive fields in data points to accept formulas would allow administrators to enter formulas that reflect the real-world logic behind the actual multiplier/additive (internally stored/used as the simplified results of the raw formula).
For example, we have pressure sensors read as 4-20mA analog inputs, multiplied to convert to feet of head,
So multiplier would be something like '25*2.30665873688' and additive would be '-20' (depth of the sensor) and the calculations and comments make the reasoning behind those values obvious (or at least reasonably understandable) to a new administrator (including one who hasn't had to think about it for a few months).