Redaction Customization - rules page

Currently the redaction only looks at 15 or 16 digit strings.  Would it be possible to implement redaction as a rule based option?   I'm envisioning a rule with a regex and then an option of keeping the first/last X number of digits shown.  For example the current redaction redacts the middle of a 15/16 digit number but leaves the first 5 and last 4 present.

Reasoning for this is that some client have specific legal requirements to redact certain numerical strings in order to protect client privacy.