You pretty much answered your own question here. In fairness to the Cubs, there isn't a single team that's unlocked the secret to developing superstars internally., and those guys are few and far between Most superstar-level guys were either high draft picks or bonus babies (Soto got $1.5m as a 16 year old), and even then, you sometimes get a Kris Bryant, and you sometimes get a Mark Appel. Considering the Cubs have picked three times in the top 10 of the MLB draft over the last decade (Schwarber, Happ, Horton), they've done a pretty darn good job of building a high quality farm system.
Where we agree is that Jed needs to look externally for the superstar bat when there are no internal options, and it's unlikely that he either will have the financial backing to do it or that he'd be willing to part with the pieces needed to acquire those guys.
That being said, I'm fully on Team Ballesteros. I can't tell if he's going to eat his way out of the league or what, but he's a hell of a hitter.