The big deal with Madden 2003-2005 was the fact you could create your own plays then save your own custom playbook -
and it actually worked in franchise. In 2006 there was a sub glitch so you couldn't use your playbooks in franchise, and users waited 3 years for EA to fix it. How did they fix it? By removing it!
Every game has some gameplay elements that are screwed up, but Madden 04 was very replayable. People spent years creating their own plays - we're talking crazy 3-4 blitz schemes to stop chuck & cheese. That's what modern day games lack, customization and replayability.
I didn't buy Madden 08 for PC so am not sure if custom playbooks worked in chise. I didn't buy it because PC Gamer slammed it for having comeback AI in their review.