squale,

The Good:
You can tour a path, but the path you want to tour should be the first item checked in your Places folder. This should move along the path at a set speed independent of the number of points you have.
The Bad:
The tour is at a constant height (can be configured in Tools> Options) and angle of view. I try and set the altitude equal to the cruising altitude. If I want to see take off or landing, I try and break my path up into segments. This way, I don't have to go through the whole thing if I just want to review the landing.
The Ugly:
I don't know when this feature might be added. I would also like to have this feature. However, I would prefer that it be something that is in the KML file itself. That way the tour will be the same for everyone independent of their local settings.