Migrating to Cloudmin platform - need advice

We currently host about 500 - 600 web sites for our clients. Right now we have two dedicated web servers, two dedicated mysql servers, a dedicated mail server, a dedicated spam/virus server and two dedicated DNS servers.

Here’s what I’m planning for the Cloudmin platform:

control1 - primary Cloudmin manager, primary DNS server
control2 - secondary Cloudmin manager, secondary DNS server
mysql1, mysql2 - two dedicated machines only running mysql
web1, 2, 3, 4 - spread out our domains out over 4 servers (compared to two now)

First question: can mail be setup using cloudmin services so I can have a dedicated mail server? Or do mailboxes live on the virtualmin instance with the web hosting for each domain? I see that i can run spam/virus using cloud services, but it’s unclear about mail.

Next question: Can the two mysql machines be setup to replicate as master/slave or is that outside what virtualmin can configure for me?

For domain replication, can you specify a target for replication? For example, if we have web 1, 2, 3 and 4, can I have 1 replicate to 2 and 2 replicate to 1, then have 3 replicate to 4 and 4 replicate to 3? Does that make sense?

Bonus question: All my boxes will be 2 cores with 4GB of RAM. Is this sufficient? Or would you bump up cores or RAM for any of those services?

Super bonus question: can anyone point me to a guide for migrating mail from an old server to a shiny new virtualmin instance?

Does anyone offer consulting for helping us get this platform launched and help in migrating?

No one has any quick advice?