How can we improve WHMCS?

As a hosting provider, it would be beneficial to us for have increased control over the Domain Validation method the system chooses for certificates, particular RapidSSL certificates.

We sell some services via Plesk which do not include HTTP file serving, for example DNS-only hosting.
Currently when WHMCS identifies the certificate order is an addon beneath a hosting service or in a Client Account with a hosting account matching the Domain, the system attempts automatic approval via HTTP file-based authentication.

For products such as DNS-only, there is no HTTP service available, as a result the automatic approval cannot be completed and the certificate is not issued.

At present the client or an admin admin must go to the certificate and click "Change Approval Email" to trigger Domain Validation via email instead.

We'd like a way to indicate to WHMCS that File or DNS-based Domain Validation is not going to be possible for certain products, so that it defaults to Email-Based approval.
Perhaps the Product Type could be used?
- Shared Hosting = File or DNS-Based Approval
- Reseller Hosting = File or DNS-Based Approval
- Other = Email Approval