A full modern team site is created for you! Not any different from other modern team sites! I guess you are talking about the classic sites which MS is now moving away from! Modern is getting more and more features over time though
At Microsoft Ignite on Tour in Berlin, there was confirmation that Sharepoint sites like communication sites will be visible within Microsoft Teams and you should be able to see this webinar on this site at the Ignite on Tour section: it is TMK40 I think but the title has Teams, SharePoint and OneDrive in it. During 2019 the integration between Teams and SharePoint is going to be a lot greater.