Which hot backup tools for MySQL InnoDB database : Percona XtraBackup, Zmanda Recovery Manager Enterprise or Community or…?
Disclaimer: I work for Percona and am one of the Percona XtraBackup developers.

You'd need to try the options and see what works best for you.

Given your needs I'd evaluate Percona XtraBackup first. It will perform the full and incremental hot backups just fine. In fact, Zmanda Recovery Manager uses Percona XtraBackup as its backend for the hot InnoDB backups.