Honestly from the last Sega Sports games I played, they need to do something serious about difficulty. I always play hardest setting on sports games, and eventually they stop being competitive, but Sega's games are too similar from year to year, once you've mastered the hardest setting in NBA 2K for the Dreamcast all the future titles are too easy.
At least EA adds enough play changes that you've got to learn some new skills to win on the higher settings. Look at NBA Live 2003 versus 2004. The control scheme is so entirely different, it feels like an entirely different game. The Sega games just feel like the same damned title with updated rosters and better graphics. +