Despite finishing at just 73-89, the Phillies actually significantly outperformed their run differential: their Pythagorean win-loss record, a measure of where they "should" have finished given runs for and against, was 66-96. Now, you can dismiss this as a bunch of mathematical hocus pocus. After all, the only win total that matters is the actual win total. And that's true. But when it comes to planning for the future, it is usually helpful to do so with the most accurate appraisal of the present in mind. If you overestimate the strength of your roster based on the previous year's performance, you would seem to be susceptible to underestimating the level of improvement that is necessary to upgrade said roster to your desired level.
The Phillies averaged 3.77 runs per game last year (610 total) while allowing 4.62 runs per game (749 total). In an average baseball season, that was the performance of a 66-win team. Last year, it took 90 wins to make the playoffs. That would suggest that Ruben Amaro Jr. and Co. should enter this offseason believing that they need to make this roster 24 games better in order for it to become a playoff-caliber roster. In unscientific terms, that means scoring a lot more runs and allowing a lot fewer. How many more runs they need to score depends on how many fewer runs they end up allowing, but the lowest-scoring NL playoff team was the Pirates with 634 runs, an edge of 24 on the Phillies. The NL league average was 649 runs, 39 more than the Phillies. The NL champion Cardinals scored 783 runs, 173 more than the Phillies. So there are some starting points.
How does a team score runs? Reach base more often or hit for more power. Often, the two go hand-in-hand. The Phillies reached base 1,825 times in 2013, third-fewest in the NL (perhaps not coincidentally, their run total was also the third-fewest). Meanwhile, they finished with the second fewest total bases*. The Phillies reached base 77 fewer times than the Pirates, 89 fewer times than league average, and 209 fewer times than the Cardinals. They finished with 164 fewer TB* than the Pirates, 108 fewer TB* than league average, and 212 fewer TB* than the Cardinals.
Recapping to this point: The Phillies need to improve their roster by 24 runs. To do so, they need to score more runs and allow fewer. To score more runs, they need to reach base more often and tally more bases when they do reach base (aka hit for more power).
All of this stuff is pretty intuitive.
Let's say the Phillies can realistically plan on some improvement at first base, where they hit just .239/.299/.396 with 300 TB* and 203 TOB in 680 plate appearances. Let's say Ryan Howard gives you what he averaged in 2010-11, which was 376 TB* and 237 TOB (extrapolated over 680 PAs). You just gained +76 total bases and +34 times on base. But where else are you planning on seeing a dramatic improvement? The short stop is the same. The second baseman is the same. The left fielder is the same. The third baseman is a rookie.
Let's say the Phillies can realistically plan on some improvement at catcher. Let's say they throw out Carlos Ruiz's last two seasons as outliers on opposite ends of the distribution and instead plan on something similar to the averages he produced between 2009-11, which were 210 TB* and 160 TOB in 428 PAs. And let's say that in the other 197 PAs their catchers will accumulate they get production similar to last year, which was 81 TB* and 58 TOB (extrapolated over 197 PAs). That's 291 TB* and 218 TOB out of Phillies catchers, compared with 260 TB* and 186 TOB last year. So they would be +31 in TB* and +32 in TOB. With Howard, that's a combined improvement of +107 TB* and +66 TOB. That puts their power right around league average, but they are still -23 in TOB.
Now, let's say right field is the only position that they upgrade on the free agent market. That would mean Revere in center field, Brown in left field, Howard at first base, Utley at second base, Rollins at short stop, Asche at third base and Ruiz at catcher.
If the new right fielder happened to be Carlos Beltran, and if Beltran gave the Phillies the same production he gave the Cardinals last year (311 TB* and 203 TOB in 600 PA) and the Phillies got the same production out of their right fielders' remaining 54 plate appearances (24 TB* and 16 TOB). That would leave them at +40 TB* and +20 TOB over last year at right field and a combined improvement of +147 TB* and +86 TOB with Howard and Ruiz.
So we can roughly project that the addition of Beltran (assuming production on par with last year) and the specified improvements of Carlos Ruiz and Ryan Howard would leave the Phillies with a league average offense, assuming all other variables on the roster remain unchanged. But they would still be -17 in TB* from where the Pirates were this year and -65 from the Cardinals, plus -3 in TOB from league average and -123 from the Cardinals. And that's with the two big assumptions that Ruiz and Howard will give you what they gave you in 2011.
Could it work? Sure. But would you bet on it working? Or would you rather try to add some more TB* and TOB? We already did it at first base and catcher, where the aforementioned improvements by Carlos Ruiz and Ryan Howard would trump any available on the free agent market. We can't realistically do it at second base or left field, where Chase Utley and Dom Brown are coming off pretty darn good seasons. I don't think we can realistically do it at third base, because Cody Asche is an unknown at this point. Like Asche, Jimmy Rollins is a huge wild card. If you are comfortable betting on a bounce back year from him, that's fine. But if I was a general manager, I would be all about risk minimization at this time of year. And one way to guard against struggles by Asche or Rollins, or something less than the aforementioned improvements out of Howard or Ruiz, or a sophomore slump by Dom Brown, or an injury to Chase Utley (or to anybody, for that matter) is to add more offense at another position. And the only position where they can realistically add more offense, given their current personnel and the personnel available on the free agent market, is center field.
One option is Curtis Granderson. Let's say both Granderson and Ben Revere got the 675 plate appearances that Phillies center fielders recorded last year. Let's say Revere produced at his 2013 level, the best of his career. And let's say that Granderson produced at his averages over his four seasons with the Yankees. Both players would reach base the same number of times, since their on base percentages in the given time periods were identical. But Granderson would accumulate +115 TB* over Revere in the same number of plate appearances. Same number of plate appearances, same number of times reaching base, with one player creating 115 more total bases. Why in the world would you not look to add that player? Revere would be a fine bench player, great depth, and a dangerous late-game pinch-runner. Both are left-handed hitters, so that cancels out.
Now, I would look at add a right-handed power bat in right field in addition to Granderson. And if it came down to either/or, I'd probably go with the right-handed power bat (depending on the specific player, of course). But the Phillies should be trying to do both. And if they can't do both, they should look at a lottery ticket like Chris Young, who at the very least would offer right handed power and center field depth on the bench.
Again, Revere is a fine player. But the Phillies' options for upgrading their offense are limited. And center field should certainly be on the table.
*For our purposes, I'm including walks and HBPs in total bases (worth one base each, obviously). Conventional TB is 1B*1+2B*2+3B*3+HR*4.