I have zero drum loops in Rock/blues. For instance, Live Edgey Drums are totally missing.
Live Edgey Drums have not been part of GarageBAnd but are installed by the Jam Pack 1.
Did you have the JamPacks installed for your previous GarageBand version?
If you made a clean install and erased your previous GarageBand installation, you need to reinstall the Jam Packs or restore the loops and the instrument library from GarageBand '11.
If you did not make a clean install and your old GarageBand '11 is still installed, it should suffice to rebuild the Loop Index. Click the drop down menu at the top of the Loop Browser and select Reindex all Loops.

Also, make sure that the GarageBand preferences are set not to filter the loops.
"Loops > Keyword Browsing > Filter for more relevant content" should be disabled.