The thing with mono is to consider the tones - with colour work similar tones separate because of the colours (sorry to teach grandma etc) but with mono it's all about light & dark. For me, the tones here don't give the subjects of these images body or volume - it's variations of grey on grey. The first breaks this a little, but the patch of blown sky and the inkiness of the bottom of the image don't provide that same sense of size that the picture would have in colour. In the case of these, to an extent they need much more over-cooking in mono to emphasis the size and majesty of the mountains, and your development is terribly polite.