This is nothing to do specifically with Dynamics AX :-) but this is something that caught my attention and I decided to try it out and share it and this can definitely be used in an AX environment to conduct a health & BP check on the AX SQL Database. The SQL Server team has released the SQL Server 2008 R2 Best Practices Analyzer (BPA) tool.
BPA is designed for administrators who want to determine the overall conformance of their SQL Server instances and topology with established best practices. BPA examines your SQL Server instance for system events, reviews login permissions, scans your SQL Metadata for advisable settings, and recommends solutions to items that do not conform with established Microsoft best practices.
There is an AX Security Hardening guide available from Microsoft but this is something extra which can definitely be used. I tried it on my AX Environment and it provided some nice results.
To contact me for any clarifications regarding any posts / information, please mail me at arijit [dot] basu [at] gmail [dot] com