It can solve quite a few things, FC housing should not be a thing to make a FC going, instead instanced guildhalls and the likes that could be done a bit Island Sanctuary style, though with an instanced house you can upgrade to large or something.

Can or should be able to be accessed your grand company HQ and maybe permit characters to be a member of more than one FC as well a bit like you could in Elderscrolls Online... that was one of the nice features.