"Making it work specifically with the filter deconstruction planner mod could be tricky, because there's a million mods that you might want it to be compatible with."
Well I don't think there are that many other mods that modify the deconstruction planner. It's the only one I know of. And it's fairly rare that a mod needs to know when an entity disappears compared to mods that needs to know when an entity is built.
Another thing. Since some objects are ok to place instantly and others are not, it would be nice with the possibility to select which ones should never be instantly placed even when the mod is set on instant place: on. Then my robots will only build the ones that need to be placed by robots and everything else would appear instantly. Might be a bit of work though.