[D] Does anyone know of any comparisons of the effectiveness of different neural network "shapes"? • r/MachineLearning

I wouldn't recommended starting with a set solution in mind for ML problems, let alone a specific NN shape. From my experience the effectiveness of ML solutions are loosely correlated with your intuition on what will work (every problem is unique). If you're trying out an NN solution, I find it's best to start with a wide-NN with lots of redundancy, so that that you can search through the solution space from multiple locations quickly. You can then start iteratively trimming neurons that don't contribute to the best output and retraining until left with an locally-optimal solution. If it happens to be an hourglass then so be it, but in terms of general effectiveness, the thinner a NN is then the more specialized (and limited) it will be.