First or Third Person RPG

So I was wondering what do people prefer when it comes to open world RPGs. I’ve seen the majority of AAA games of this genre being in third person. But, then there is Skyrim/Far Cry 1,2,3 which are all in first person. So, why are most open world RPG in third person?

Also:

-which would be easier to create? (beginner) (game combat would probably be >80% shooting)
-better for a more immerse experience?
-if you went for third person, do you prefer “over the shoulder view” or a view from about 2-3 meters behind (GTA etc).