It seems like some functionality changed between Moss 2007 and our new SharePoint 2013 site,
Is there a easy way to list sub sites into the quick launch automatically or as an alternative create a list that I can display as a web part?
i think you need to activate the publishing feature:
Activate publishing at the site collection level
1.From the root of your site collection, click Settings Small Settings gear that took the place of Site Settings. > Site settings.
2.On the Site Settings page under Site Collection Administration, click Site collection features.
3.On the Site Features page, scroll down to SharePoint Server Publishing Infrastructure and click Activate.
Once publishing features are activated, subsites inherit them automatically. But, if you built a site before activating the publishing infrastructure, you’ll have to manually activate it for each site.
Activate publishing at the site level
1.From any page within the site, click (gear icon) Settings Small Settings gear that took the place of Site Settings. > Site settings.
2.On the Site Settings page, in the Site Actions section, click Manage site features.
3.On the Site Features page, next to SharePoint Server Publishing, click Activate.