I am looking at switching from Code Igniter to Laravel.
We deploy a large amount of sites, using our custom admin panel.
This is setup as two installations of Code Igniter,
You basically have (simplified, we actually use HMVC on both the main site and the admin panel, but this gets the point across)
You may have already pondered this, but I think it would be best to use an admin bundle, considering that bundles are all part of the core system. It's good for SoC and for simplicity (ease of use).
The admin panel could then find all bundles (except itself, of course) to read and write configuration entries, such as those of a blog bundle.
An alternative would be to place the admin panel into your main application, by routing specific commands to various admin controllers (don't forget that you can put controllers into sub-folders). For example, you could route, using
admin/pages/edit/152 to the
pages.php controller in
application/controllers/admin/. You could even manage your various bundles/snap-ins using this approach, by means of scanning the bundles directory, as mentioned before.