Can I word notifications differently based on status?

Yes! There are two ways to achieve this:

Firstly, you can add two (or more) notifiers (e.g. email), each with the desired text, and assign one to changes, failures and/or recoveries, as appropriate.

When adding notifiers, you can specify on the Options page what kind of status they're available for (they can be for multiple kinds, too), then in the Edit Test window's Notifiers page you add multiple rows, each specifying a different status and notifier.

Secondly, you can use variables to use one notifier for different statuses.

For example, the variable {TestStatusPhrase} will output a word or phrase like "failed" or "recently recovered".

See the Service variables, Filter variables and Notifier variables in the Simon Help for lists of available variables.