The fact that you suggested a PB value of 70 as a realistic limit shows you have no real grasp of what a good team has. In a 24 team traditional league last year I started the season with a PB value in the 80's or low 90's, I put my best team on the field until I started trading for draft picks late in the season, and my team ended up with a lottery pick.

Forcing a PB value limit of 70 on everyone would be like imposing a salary cap of $30 million per team in major league baseball.