Hi Luca,
I want to let you know that we built SharePoint Migration tool MetaVis Migrator for Office 365 that can copy on-premise or hosted SharePoint sites (including Foundation) to Office 365 SharePoint. The tool can copy entire sites with sub-site hierarchies, content types, fields, lists, list views, documents, items with attachments, look and feel elements, permissions, groups and other objects. The tool preserves created / modified properties, all metadata and versions. It looks like Windows Explorer with copy/paste and drag-n-drop functions so it is easy to learn. It does not require any server side installations so you can do everything using your computer or any other server. The tool can copy the complete sites or just individual lists or even selected items. The tool also supports incremental or delta copy based on the previous migrations.
Free trial is available: http://www.metavistech.com . Feel free to contact us.
Good luck with your migration project,
Mark