Allow more customisation, e.g. the option to have 'dear' instead of 'hi' in the email.
The ability to customise and use html in the email and on the form.
Make choosing purposes a required field so that people cannot update without selection 'yes' or 'no' for each purpose.
Send emails even when an email is tied to two records - if they are tied to a company/trust or foundation then the email should assume they are updating their individual record. Maybe ask them to choose on the form if it is on behalf of an individual or an organisation.