Yes and no. I think an intelligent designer must exist for evidential scientific reasons, not simply because science hasn't yet explained the 'gaps'. I think there is enough positive scientific evidence to assert that life as we know it could not have come about by chance, that there is something else behind it. I think science is just as guilty of resorting to noumenal explanations by theorising about unprovables, such as multi-universes, etc.
But ultimately this is a thread about metaphysics, not pure science. Our current level of science cannot even begin to approach metaphysical questions. And we know that science by its materialist bent is strongly biased against metaphysical explanations.
The first and hardest thing to do is admit biases and try to resist them, because it warps everything. Philosophy is better suited to examining metaphysical questions because it tends to sit between religion and science, and its intellectual rigour of logic tends to mitigate biases. Philosophically, the Problem of Evil destroys theism, as I alluded. So I'm no 'god of the gaps' proponent, but I do think that the scientific evidence as it is unfolding is becoming increasingly problematic for traditional evolutionary theory to explain away.
Put it this way: as science is slowly but surely filling in the 'gaps', the evidence accumulating is suggestive or more complexity and design than otherwise. To counteract this, physicists are having to resort to ever more metaphysical speculations that are just as 'out there' as the idea of an intelligent designer. You have to follow the evidence where it leads you, but bias will draw you back to choose the metaphysical theory you favour.
God = metaphysics
Orthodox scientic explanations on origin of life = metaphysics
Big bang theory = metaphysics