A way for the system to send a reply to customer if they haven't replied after a certain amount of time e.g 24 hours or 72 , Also the ability to mention an another agent via the "@" symbol to allow them for a comment but not necessarily watch the ticket .!
To remind customers, you could change the status to "Awaiting customer response" and set up a Supervisor rule as follows :
1) From Admin > Supervisor, create a New rule
2) Set Condition - Hours since customer responded is 24 hours
3) Set Condition - Status is "Awaiting Customer Response"
4) Set Action - Send email to Requester - You could configure the message you want to send the requester here.
Also, make sure that the observer rule "Automatically reopen tickets when the customer responds " is turned on.
For looping another Agent into the ticket, you could notify them using private notes. But am afraid you would have to select the agent's name from the list. Let us know if you require further assistance. We'll do our best to help you out.