I used to agree with you 100%. I was excited by the Randy Moss move in 2007, but confused -- why do we need a big play receiver? We won 3 Super Bowls with scrubs and Antowain Smith, and a smashmouth defense.
Here's the thing -- that was then. I think the league is a bit different now, moving towards a more pass-focused game. I also think relying on our old system is a bad move -- clearly, over the years, teams figured out the Patriots dink-and-dunk offense.
If you want to stay on top, in anything, you need to keep adapting and evolving. Getting a true #1 receiver would continue that evolution from where Randy Moss left off (actually, it'd be way better than what Moss had to offer us, because Jones is more of a physical threat, and not as much of a head case).