I can't speak for Bohr's meaning there, but it could be that the point of complementarity is like the complementarity of momentum and position in the uncertainty principle-- that knowledge of one precludes knowledge of the other, yet both are present and can be known independently. Thus the idea would be that you can describe a living thing by all its parts, but in the process losing their united function, or you can consider the united function, but then you cannot understand what is happening at the molecular level. It goes deeper than the whole being more than the sum of parts, which can be said for a good poem for example-- it is more like, to know the poem is to lose information about what words went into it, or to know every word in the poem is to not be able to understand the poem. That's a much trickier principle, found only (so far) in quantum mechanics.
No.
That is also an example of an "emergent property", so is part of what Bohr probably meant, but not all. The emergent property is seen in a lot of places, like your examples or my poem, but complementarity was only even imagined in Bohr's day.Not to my knowledge, though Wigner did think along those lines. Rest assured there are no quantum phenomena that benefit from the inclusion of consciousness, and no predictions are made that way.