Domain properties in the new GSC

Two questions related to GSC. The first one is general and the second one is situational.1. I understand Google rolled out domain properties in the new GSC. I have not used this yet but plan to in the future. Does anyone know if there is still a need to set up a preferred domain? Do you know if it is still recommended to setup multiple properties for all versions of the site? If the only subdomains or domain variants that exist are https vs http and www vs non-www, can you ONLY setup a domain property, view everything in there, and not worry abut telling GSC which version is preferred? Sorry, can`t find a good resource right now. 2. I recently was tasked with looking at someone`s GSC. Right now there are two properties, one for https://www and one for http://www. So both are www, but one is secure and one is not. The site resolves to https://www and there is no domain property setup. When I go into both properties, performance data is split between the two. The XML sitemap was submitted in the non-secure version, which obviously needs to be changed. However, since the preferred domain setting only tells GSC www vs non-www, is there anything else I need to do to make sure https://www has all insights and http has nothing? The switch to https:// was done a long time ago, redirects are good...etc. I know that I could most likely setup a domain property and see combined data there, but since there is a clear reporting issue, I don`t want to do that right now.