Idera SQL Check
This can be a handy tool to install on the SQL server running a vCenter database I’ve found in the past if you don’t have a dedicated DBA resource on hand. It can help with some of the more obvious problems that crop up. The tool’s limited to 1 server and 20 health metrics. If you want more, you have to pay for SQL Diagnostic Manager.
Idera SQL Fragmentation Analyzer
Another free tool that can help with fragmentation statistics for a database.
Idera PowerShell Scripts for SQL
If you’re into PowerShell scripting, these free scripts might be useful.