I know that Google prefers JSON-LD over microdata, that is a given. I intend to use both as much as I can. I also know that the Earth rotates around Google and the Sun is just a moon. However, from a performance perspective, which is more effective overall (I assume microdata) and is JSON-LD a requirement for things like Google+, Google Maps, and Google My Business? I am hoping that this question would be a semi-authoritative update on the topic of encouraging knowledge graph cards and any offering Bing might have. If there are any other requirements besides mark-up, that would help as a side-note.
I have created a fairly simple one-page mobile-first website which I intend to expand later with content for renters and landlords as well as comments on rental real-estate law and tricks of the trade. I intend to use Google My Business and Google Maps as much as possible for validation and ranking. I will not be using HTTPS. The domain name will have a private registration. I want to build my trust metrics to compensate for these factors.
I ask these questions because it seems that mark-up has changed somewhat lately and how people use them as well as how the SEs see them. I do want to encourage a knowledge graph card right out of the box. I do have rental listings online now and doing a search for the address does result in some major real-estate rental sites having a listing as a result of past advertising. I expect/hope that Google will see this as validation. Who knows?
I am just dotting my t's and crossing my i's and seeing if there is an official word out there on the subject.