Coming off a season where they won 108 games, winning 92 was a disappointment. I think its fair to expect a let down, with all the enthusiasm of the prior season and the season getting off to a bad start with the drug suspension of ace Dwight Gooden.
The Bob Ojeda injury kept the Mets from having as formidable rotation as the previous season. The bullpen kind of let the team down, probably because Roger McDowell and Jesse Orosco wore out after all the work in 1986 and the postseason. Newcomer Randy Myers, despite 92 strikeouts in 75 innings pitched, was inconsistent pitching to 3.96 ERA while McDowell and Orosco pitched to ERAs of 4.16 and 4.44, respectively. Rick Aguilera was having a breakout season going 11-3 before an injury shut down his season. Terry Leach went 11-1, both relieving and starting, but would have been better suited providing depth as a full-time reliever.
Offensively, you can make a case that the team was better than the previous year. 3B Howard Johnson had a huge year, hitting .265, 36, 99 and newcomer Kevin McReynolds, though fans didn't embrace him because he was quiet, hit .276, 29, 95. Those were huge additions to a lineup that already included Keith Hernandez (.290, 18, 89), Darryl Strawberry (.284, 39, 104) and Gary Carter (.235, 20, 83). Also factor in Tim Teufel's .298, 14, 61 season, when he was .247, 4, 31 in 1986 and this was easily the best offensive team in the league. Only Carter notably had a better season in 1986 (.255, 24, 105). It wasn't good enough to catch a Cardinals team that got back power hitting 1B Jack Clark after missing him for a good amount of the 1986 season.
I would take the 1987 Mets offense over the 1986, but the pitching was much better in 1986. Not having Gooden to start the season and the injuries to Ojeda and Aguilera caused for too many moving parts. The staff was set up to be deeper with the additions of Randy Myers and Terry Leach, but by the end of the season, everybody was overworked. They used former Indians SP Don Schultze to start some games, similar to a 2008 Brian Lawrence. They even acquired John Candeleria from the Angels to make a couple of starts in September. In the end, the Cardinals won because they had they better and healthier pitching staff.
Top to bottom, I actually liked the 1987 Mets team, depth wise. The lineup had a 1-7 that was probably the best in their history, while maintaining a deep bench. Extra quality arms, such as Leach, Myers, David Cone and John Mitchell were supposed to control the workloads of guys like McDowell and Orosco. That didn't happen.
I wasn't old enough to enjoy the 1986 Mets WS victory first hand, but I very well remember the 1987 season. Though it was a huge disappointment not returning to the postseason, it probably made them better in 1988. Unfortunately, 1988 was the bigger disappointment, not beating the Dodgers in the NLCS where they were heavily favorited. 1987 was the first full season I remember, being 7 years old. I can't believe its been 25 years since then, and 26 since the team's last World Series Championship.