Business exception reporting I work in an analytical role at a a large financial services firm. We do a ton of daily reporting over metrics that rarely change in a meaningful way from day to day. From this daily reporting, our management is required to extract what was important yesterday and what important trends have developed / are developing over time.

I want to change this to a model of daily exception reporting and weekly trend reporting. 

Features might include: 


User report consolidation (so there's only one daily email)
report ordering based upon level of variance from past performance (see the most important stuff first)
HTML email support (with my audience, pretty counts)
Web interface to allow preference changes, including LDAP support (make administration easier)
Unsubscribe feature at the report level


Here's what I'd like to know:


What are the practical problems I might run into?
What is the best way to display the new reports?
How should  I define an "exception"? How can I know if my definition is a good one?
I assume I'd be using a mix of Python, SQL, and powershell. Anything else I should consider, e.g. R? What are some good resources?
Try exploring the rich field of "Anomaly Detection in Time Series". Control charts and CUSUMs (or cumulative sum control charts) might help you.

Simple Bullet Graphs might be all you need. Based on historical data and domain knowledge, define normal variance. Then make it clear to stakeholders when the current value is outside of predefined ranges.

Stephen Few is an expert in business dashboards. Any of his books will help you.

If you are open to R, try Shiny to create simple interactive web applications (It is very straightforward). There is also an open source package for anomaly detection, both local and global.  

Create quick prototypes and get feedback!