Phillies will be sellers, not buyers, it doesn't take a genius to see that one or two players won't make a difference, and the mistake was thinking that Harper was a difference maker, given his youth, and the low cost (on a yearly basis), he's still a solid addition for the long haul.
But this team has completely revamped its scouting and minor league organization and that will take years to bear fruit. It took a decade of drafting ineptitude to bring this team down, it will take a few years to build it up.
Worst thing they can do is chase a wildcard spot if the goal is an eventual WS.
Best thing they can do is move out players not in future plans for more young arms, as we've seen, buying veteran pitchers is an expensive crapshoot (Arrieta, Robertson, Neshak, Hunter). Keep stockpiling young arms in AA and AAA ball and show some patience.
Notice the Dodgers have let their share of veteran pitchers walk, you have to continually develop pitching b/c it has a short shelf life. If you build up a core of starting players, you can field a competitive team for a long stretch, but even when you have top starters, they can fall off the cliff tomorrow (see SF, Mets).