It's just my opinion, but I think the last really great song he wrote was "Jenny Wren" on the previous album. I find that song complex and beautiful. Before that, I havent been that impressed w/ his output since the great "Mull of Kintyre". His first five solo albums are all top-notch, IMO (yes, even "Wild Life")
For me, Paul's compositions were more inspired (and therefore better) when Linda was still alive and well and w/ him. These days, in my estimation, he seldom "hits one out of the ballpark" (like he did w/ "Jenny Wren"), but when he does, it's usually a great piece of art.
Needless to say, all his Beatle-era work is beyond reproach.
-MMM