You still have to check the entities flags each frame regardless of what they are. This is a time consuming task if you have 500 entities.
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If not, would it be possible to have a feature in the future which completely shuts the engine off to an entity except for rendering.
Remove Object would be a good way. 
The draw list / tree assigns what needs to be rendered / how and where, the render does not keep that data from frame to frame...
Ken
