1. Are these photos reduced to 0.7 MP versions of the original 18 MP image or are they unreduced crops from the original? Because if they are reduced (resampled) versions, it is just about impossible to say anything about the noise in the original.
2. If you could describe what you did, others might be better able to say what they would do differently.
3. This image isn't the best example for this sort of question. The thing about successful noise reduction is blurring out the noise without blurring out meaningful image detail (or at least minimizing its loss), but most of this image is out of focus areas where detail has already been lost so losing some more isn't so terrible. Moreover, the polished metal of the horn is certainly not a textured surface that you would need to try to protect. The hand is, of course, textured, but OOF. That leaves the paper, which is finely textured but that texture may have been beyond the resolving power of your lens and sensor (and certainly was if these are only crops). Most normal paper texture is also beyond the resolving ability of our eyes unless we get very close, so we tend to think of it as smooth and the detail that needs to be protected in such a photo is if there is very detailed printing - which is not the case here.