I ran around the zone the other day. It didn't feel small to me. It's not huge like cyrodiil but it didnt feel small. I spent at least 10 minutes inside one building in the first city you port to (Alinor?).

The larger cities are hugely complex and detailed and took a lot of work. The forests are beautiful and very detailed as well.

The whole zone is gorgeous. Didn't do any quests because i didnt want to spoil it prior to launch, but I am looking forward to playing it.