How can we improve WHMCS?

Hi.
because, some registrars have the reservation feature for domains, the idea is to add this functionality of "reserve domain" at specified registrar for specified days.

how I see this in deal. Customer make a new domain order. At the time when invoice are created, whmcs will send, using defined by module, RESERVE command to registrar, and will set for domain "status = RESERVED" , also will set next due date for XX days specified in "Domain Registrars" (picture 1)
if order is payed in time, the whmcs will proceed wuth domain registration,
else , status will be automatically set to changed to CANCELED.