Backup-to-disk Plan

Dear Everyone
I am planning a new backup strategy of our 10 windows servers to disk. The servers are running in VMware and the backupserver is a separate physical server in a different location with plenty of disk and BackupExec12. I have installed BackupExec Agents on the windows servers to be backed up.
Some of you might say, where is the tape? The answer is; I have skipped it. Right or wrong.

How can I plan the backups to have a safe recovery plan for my servers?

My initial plan was:
Daily incremental, Save for 10 days
Weekly Full, Save for 6 weeks
Monthly full, Save for 18 months
Yearly Full, Save forever

Is this a good plan? Or do you have another succestion? Please let me now!