@broadstairs:
From my somewhat simplistic point of view, I only really monitor SNRM and ES on a very regular basis from my 3 RPi's on the lines I look after, I do snapshot SNRM, CRC's, ES's and Conn Speed's on a 2 day graph page basis, also Avg Errors text page at the same time scale.
If any cause for concern is noted or a router (DLM) re-synch should occur (notified by e-mail) then all the additional parameters can be examined from DSLStats historical data.
Obviously not as good as MDWS monitoring when this was active where direct, live comparisons to all other users lines could be made and any line issues could be viewed / diagnosed by the more knowledgable forum members.
Once again, many thanks for sharing your php/ftp script, I run this on my Win 8.1 desktop PC (php with Apache) and find it really useful, once the archieved data files are loaded to the appropriate areas viewing becomes very easy.