Right now we're kinda winging it, but we should be leading by design here.
The default layout and node are in the spark_demo module under the spark project. The module itself has a page_manager page exported and a panels layout exported. The page manager page itself includes the panel embedded. By editing and adjusting these, it should be relatively simple to modify the experience. Re-exporting and copy-pasting the exported PHP into the files should be enough to update. If the path of the page_manager page is changed, the spark_demo.install should be changed too to reflect the new front page path. Otherwise only the spark_demo.module file is interesting at the moment.
Hope this little direction info helps.
De-prioritizing this for now. Focusing more on functionality than OOB experience for the time being.
Meh. We no longer really care.
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