You're right. There may be one or two bigger names cast in these films, but it will be (hopefully)largely unknowns. For those few of us who enjoy this topic, the fun is in envisioning who MIGHT work in certain roles, based on their prior experiences.
Clearly there would have to be a huge budget for the sets and effects for a film(s) like this, and I wouldn't want to see any of that sacrificed for hiring a "A Bridge Too Far" kind of cast. I would much rather see some unknowns catapult their acting careers by getting cast in these roles, but I think it's entertaining to discuss who might be able to pull off these roles that we all hold so close to our hearts.

I disagree with you about Connery though. I don't care if Gandalf talks like a Scot, I think he should have some kind of accent. It didn't bother me in "The Hunt for Red October," and I think he's perfect for the role.