I work regularly on an OBIEE repository with 100+ facts and 200+ logical table sources.
Every time I add a new dimension, I have to go one-by-one to set the logical level for that dimension in each and every table source.
Is there any way, when adding a dimension, to default all LTS to a specific logical level?
Same answer as for cross-post here:
No.
A model this size is probably not the best approach in an ideal world.
The only option you have is to look at a script-based approach. There is a supported API for modifying the RPD metadata, (and here too), but it'd be pretty easy to screw things up, doubly so given the size and complexity of your existing RPD. You can see an example of it in action in a blog I wrote here. Note that all I change in that blog post is the value of an existing repository variable. To add in additional content, with the issue of GUIDs etc, gets very hairy indeed.
tl;dr : sit tight, and keep clicking, unless you're feeling brave