CRM with Dialer needed

I am looking to build a new CRM to mimic the CRM we are currently using which is a lead manager and phone dialer, all in one. This CRM must do the same as what is outlined below but should have more functionality and flexibility as well. The system we are currently using does the following: Leads are pushed (one at a time) into our CRM/Dialer real-time from lead providers via XML post; the leads are distributed to agents according to specific rules for each lead campaign and which agent is available. Actions are taken on each lead in order to execute specific tasks (like send an email, etc) then the status will change according to the action taken. The order which the agent calls the leads are dictated by rules we set for prioritization of their leads. Each action taken will change the status of the lead but limitations are set so that leads must be archived according to the rules and maximums we set. When the agent logs into his/her account, they see the leads according to the prioritization rules. They can click on the first customer and their phone (asterisk based PBX with Grandstream phones) will begin calling that lead. After the call, an action is taken, then the agent clicks "next lead" and the next call is dialed. Emails are pre-written and are automatically sent out upon specific actions taken. Additional features I am looking for.. The manager of one office has view of his agents' reports and data and can see any of the same data of the managers below him or her... but can not see other offices' agents, managers or data. Script should be written for the agents to see the scripts on screen with a basic flow of conversation (ie. if the customer says "yes" the script will go one way; if the customer says "no" it will go a different way). The last few steps, after the CRM goes live and works properly, is that I would like to create an API which posts necessary information from this CRM to my vendors CRM ([login to view URL]).