There is a lot of data and information on supported devices that is scattered around the Repicant wiki, git repositories and even Wikidata. So it's a good idea to have a checklist on what to add.
When we will have migrated to Mediawiki, we could automatically generate part of that list as we will be able to tag pages with Cathegories.
In addition if you can send a patch for the data repository to add the PIT if your device has a PIT. Additionally you can just push the commit if you have push access. If your device (also) has more classical partition tables like GPT or MBR, it is also a good idea to send a patch adding them to this repository as well. With the PIT, GPT and/or MBR anyone can write documentation on the partition table of the device. In the future that documentation could even be generated from that data.
If your device has a modem and has a modem data partition, it is also a good idea to add the list of files and their permissions to the wiki like in the GT-I9300EFSContent page. This enables to restore the file permissions. Note that while publishing the file names and permissions look safe, the file content might contain privacy or security sensitive information like the IMEI.
Additionally some projects