Before the 2006 season begins, I can say to you that the Rewards/Tier system will change a little (will be effective for 2007). Tiers was made to help us with the signing process. As the signing process changed, it is no longer necessary to have 6 different Tiers. I've also noticed that mid teams and back markers do not progress the way they should progress. For many other reasons, here are the new Tiers/Rewards :
Tier 1 - #1 in the last year Standings
Tier 2 - #2 & #3 in the last year Standings
Tier 3 - #4 to #7 in the last year Standings
Tier 4 - #8 to #11 in the last year Standings
Basically,
Tier 1 : You are champion
Tier 2 : You fight for winning a race
Tier 3 : You fight for points
Tier 4 : You fight for not being the worst team