I can see the merits of increasing from 50% of teams making it considering that a 4 team playoff was decided when it was a 6 team league. I believe our playoff formats are limited to the options in STHS, so I'd be curious to know what the options are for an 8 team league. I like giving the top seed a bye and add a fifth team so we're at 5/8 teams in the playoff.
I also think it gets sketch to have teams under .500 make the playoffs, but in a league with a lower and upper bracket for TPE, development during a season can lead to playoff success. Teams that develop should have the chance to show it off in the playoffs. Maybe a 5 team playoff would be neat to see, granted if STHS allows it.