we can receive alert via emails and there are lot of useful alert macro to get useful data. according to user experience and my experiences,i think you should consider about adding a macro to get last value (the value before the alert firing) then we can compare the value with current value (caused to fire alert) and get a more clear idea about value change amount decide whether it is major problem or minor problem.
My next suggestion is adding critical,warning min max level as module macro. so when we receive email alert we have no idea about "value deviations". so with this change as a example we can compare critical value with min and max vales and get idea 'how bad is the condition of device'.(no need of going to module details and compare with min/max levels).