Actually, juggling effectively on that map is a bit of a challenge. You have to expend a lot of additional resources in order to set up a working juggling path, because the whole map is buildable. My score, at least for story mode, is done with 22 towers. That's possibly 18 plus a couple of juggles on the final boss wave, but hardly the juggle-fest that it could be. Sal, for instance, completed the map with 138k, and 127 towers built.
Speaking of juggling, my plan at the moment is to actually do two videos for the same map (Last Stand), juggle versus non-juggle. It's the one big scoring mechanism I haven't covered for you guys yet, and one of the most boring, honestly. Still, if it's points that matter, it's a tough tactic to beat.