Hi,
The two points I would raise are:
* Don't ever underestimate your need for backups. The whole "we have plenty of availability and that's more important" argument will bite you hard the moment someone deletes a file and needs it back. Just have a look at some of the threads here regarding VDP and consider if you really want to rely on it..
* vSphere replication does not allow for HA, it's for a DR scenario and will not automate a failover in the event of a server failing. Without any shared storage at the primary site, you're not really sharing the load. If you can't invest in a decent SAN, look at VMware's VSA appliance.
* The obvious thing here will be that the better your primary environment is, the less likely that DR scenario is. Don't let the existance of the DR site convince you the primary should run on cheap rubbish.