There is a fundamental question that has no real answer.
What is more important five years down the road - - - hitting or pitching?
The obvious answer for a contender is both, but that really cannot happen without a major bit of luck and massive overproduction from your roster.
Teams have started to guard their prospects like gold bars in a inflationary world. When teams trade veterans for prospects, they would like to get young arms with high ceilings in return. Teams pay a premium for quality starting pitchers in the free agent market. So pitching is more important than hitting?
Not really, In the post-steroid era, hitting especially natural power hitters, are becoming a scarce commodity. No longer do you find a herd of 30 home run second basemen littering All-Star ballots. In fact, we are back to the days where hitting 30 HRs in a season is a real accomplishment. Every major league roster is filled with .230 hitters. When did that become acceptable? So finding quality hitting is more important than pitching?
The Cubs have made a real effort to draft hitting prospects high in the draft, then overloading with pitchers in the middle rounds in a Vegas attempt to roll a hard eight. However, as a prospect works his way through the system, it gets harder to hit better pitching. A hitter's mechanics may get changed four or five times before his call up from AAA. On the other hand, pitchers throw like they have thrown since high school. Coaches may add nuances and new grips to add variety to the pitcher's arsenal, but basically a pitcher is an organic machine throwing the baseball to home plate. A pitcher with good control will find work over a flamethrower with no command.
The problem with the Cubs is that if the convention they are vested in, hitting, as the long term plan for success, the team has more "swingers" than hitters. Free swingers like Soler, Baez, Castro may connect for the long ball more often than an average player, but their batting average will suffer. The team really does not have a solid .310 hitter in the middle of the line up. The team really does not have high on-base percentage guys either.
So do you use flawed swing hitters to acquire high quality pitching, like Cole Hamels? Perhaps, but then you have the problem of replacing hitting with less potential.
It is a vicious cycle that needs balance in order to succeed. The easiest way to get balance is to draft well year after year without complaining about the new CBA restricting loop holes. The best way to build a roster is to develop major league ready talent. But that is easier said than done. Only a hand full of franchises have that long term reputation of developing good talent year after year.