Way too many obscure names for me to enjoy this one (serpigo, Abelard, Rorschach, egg-flip).
Among the many I can't fathom:
17a Land to the west excellent - north west (7)
e-t-n--. Estonia?
7d A certain posturing no longer holds a Spanish artist up (5,4)
h-t-- and -o-a.
28d Old actor appreciated on tours one reflected (7).
I assume it's Gielgud but can't see why. I suppose gud is dug (appreciated) backwards but this is a down clue, so "reflected" doesn't work as a reversal indicator.