Grade: A
Could've very easily made my top 50 list sent to Cosmo. As is the tradition of season 2, the story, humor, and emotion is about 95% character driven, and this episode favors that style very well (so well that I'm laughing Bart and Lisa's dinner food war). The story itself is pretty sweet, as is the best episode to date about death in a humanistic way ("Homer's Enemy" is a different case), complete with the effective "dignity's on me" feel good ending. And while the humor doesn't have anything that stands out like in more comedy centric episodes, it's still pretty consistent and rarely (if ever) falls flat, from Grampa's search as to where to spend his money was very funny to me (Frink's death ray sticks out), to the Safari adventure, to his attempts at romance with Bea. Plus, the commentary on the treatment on the elderly (shown often through the dilapidated old folks home and Homer's view of Abe's romance) is ingrained into the storyline, as the best commentaries and satires generally are.
As an aside, I may be giving the episode too much credit here, but Abe's line, "You know, Jasper, they may say she died of a burst ventricle, but I know she died of a broken heart." is reminiscent of a similar line near the end of my favorite book "Captains and the Kings", and I wonder if it's intentional.