your current config is ok, no need to worry too much, for each subnet just use one pNIC, that is what the DELL paper says, and that is what i also mentioned in my first post, an one to one mapping is needed for the best practice. But there is no issue, if you have only 2 pNICS and you use only 2 portgroups. As of now any way you will have 4 paths, each portgroups can see 2 paths.
So far it is ok, no issues.
The whole poing of the vlans/subnets in IP based san is to tag the packets, and it should not be routable. Because the routing will introduce the delays and may cause SCSI time out. So the basic point is, all the storage ips should be pingable from the esxi.