Hello!
Just a suggestion: create a ISO or USB Flash Drive with a Kickstart Script for the Setup: Installation and Upgrade Script Commands (vmware.com) You can do quite a lot with "%firstboot" and it would be a clean install.
ESXi 6.7 Hosts are fully supported under vCenter 7.0 U3 (Product Interoperability Matrix (vmware.com))
Regards,
Robert