Hmm, well now it seems like it goes to solid gray instead of solid black which I think is still wrong; it looks like you're possibly clamping the occlusion to solid black and then bringing it back up after the fact, after the data in the "too dark" regions is already gone. You should probably be decreasing the influence of each occluder before summing them together, both to avoid this and because you might want to play with the distance attenuation function, etc. for each occluder rather than just decreasing the influence by a constant factor; this will give you more control to tune it to look the way you want. Even with all that in mind, it still seems like progress, especially if you're not going to rely on SSAO as your only shading.