All the teams improve from year to year. When it comes to Heros being at the top now we're supposed to believe they just got better and started playing as a team, why can't the same be true for Skywalkers improving season to season? And every single team takes players who played on other teams year-to-year, it's normal movement.
Because that was the supposed reason they were better last summer, and then they didn't play well in the fall--so what changed...?