Workspace:Hosting/WordPress

Trying to gather my thoughts on providing hosting should Cloud Sites, Rackspace's managed cloud server. My current problem is that I am not equipped as an individual to deal with the problems that arise from hosting many sites on one server. I have the sysop stuff down, but the matters of scaling and dealing with malicious traffic is not something I want to deal with.

Requirements

 * Secure login on the backend, even if it requires using a different domain.
 * Multiple account level controls, for other folks to check the server status independently of myself.

Questions

 * I can't have wildcard SSL certs on Cloud Sites, but can I have multiple single domain SSL certs?
 * Can I run an WordPress cluster without shell access?