Considering the game, or whatever, sounds highly dynamic occlusion planes don't seem like an option. Besides, avoiding developer overhead is always a good idea, manually setting up occlusion is just more work.
Depth occlusion on the other hand is a very useful tool, and indeed used by many things. There's also more complex options, DICE was helpful enough to put this out: http://www.slideshare.net/DICEStudio/culling-the-battlefield-data-oriented-design-in-practice and their requirements sound similar to yours in some way.
As for culling point light shadow maps, draw calls are often a bottleneck here along with polycount. "Efficient virtual shadow maps for many lights" extends clustered light culling, the current hotness for realtime lighting optimization anyway, to culling for shadow maps: http://www.cse.chalmers.se/~uffe/ClusteredWithShadows.pdf Unfortunately there's also an overhead to this extension, meaning you'd have to take into consideration just how many shadow maps you want going at once before considering the above.