I have a dozen clusters of hosts using 20 pNICs each. The pNICs are divided up to airgap different security environments.
Since you have the stacked switches you could use static etherchannels to your hosts. If you use etherchannel pay careful attention to your IP schemes (where possible) to ensure the pNICs are utilized in an even manner. There is a lot of information out there on how to calculate which NIC is used based on source & destination IP addresses. Etherchannel has some quirks to it that I don't like. Anyone who has been burned by a suspended NIC and link status failure detection knows what I mean.
Skip the etherchannel on your vMotion networks to use multi-NIC vmotion in an effective manner. Read up on VIFs for NetApp to utilize all the links on your IP storage network.
You could go with a dvSwitch and load-based teaming (LBT) (no etherchannel), but with so many NICs you have a lot of flexibility to physically isolate traffic types. I'm not sure paying for the enterprise plus license would be worth it.