Schierholtz is like Feldman, a good value but an underwhelming player.
I agree that they're going for an A's type team. Assuming they fill 3b with someone competent and add another reliever, we'll have no glaring holes on this team. If the kids do better than expected, the pitching staff hits it's 80th percentile projection, or Castro/Rizzo ascend to superstar status you've got a WC caliber team.
They're hoping the team does well and they can start making fun moves next winter, but not doing anything that can negatively affect the team long-term.
This is exactly what I'm seeing as well. They are trying to put a team together that will give you the "well, you know what your getting from him" type of team all the way around.
Like you said, if Castro/Rizzo/Shark can really take a BIG step forward in their progression and become legit superstars, we may not be WS winners, but we will at least be competitive and in the hunt, and maybe a move or two away from the playoffs (depending on who we go with at 3B). I also think Jackson will surprise some people this year, but that's just based on a "gut feeling", and we all know how reliable that is...
The big problem is that we kind of thought we had that kind of team last year, but someone always Marlon Byrds or Kerry Woods or Geovany Sotos. Some of the guys who look solid but not terrible now will turn in negative WAR seasons.