[Serusers] Adding services - help needed

I need help choosing how to implement different services with SER. I was thinking to use Asterisk for application services, but i don't know how the integration could be done. Here is a list of services. Could you give advice of what would be the better solution to get this ? - Let the end user hide his calling number. Is it possible with SER to choose to hide the calling number and stay anonymous. - Let the end user choose to reject anonymous incoming call. (he could active/deactivate this function via a keypad combination) - Double call with signaling of incoming second call while already on communication. - Call transfert : let a user transfer a call to another user with a keypad combination. For each case, what would be realist ? Note that i don't want to use asterisk as the main SIP router. I want to keep SER at front for routing logic thanks.