I'll start with a bit of a moan - I would have been very interested to have read those charts you produced, but couldn't do so because the print was so small and I don't think the coloured text helped either.
Apart from that though, I enjoyed it and it's good to see what I think is a general feeling that we've improved under Warnock backed up by statistics.
I agree with you about the selling of the two goalkeepers. To be fair to Ben Amos, who I was pretty critical of before he'd played a game for us, I've not seen him concede many goals that he could be blamed for, but, by the same token, it's hard to think of many outstanding saves from him either - might there be some goals he has let in that Marshall, or even Moore, might have prevented?
Regarding those defensive stats, the conclusion I arrive at when reading is that we should not be conceding as many goals as we are doing (there are still only two sides in the division who have let in more than us). Therefore, I wonder if sheer bad luck might be a factor in why we concede so many? I'm thinking in particular here of Huddersfield's second goal which would not have flown in like it did on nine out of ten occasions - also, we are conceding an awful lot of penalties this season.