Except the bonuses for rookies are meaningless if they don't spend the entire year with the NHL team, lead the team in scoring, win an award etc. Also a change from the old CBA, bonuses don't count against that year's cap anymore, they carry over to the next year. So all the max rookie ELC contracts only count 925k against the cap.
I'm pretty sure it's more strict too, as to what you can have as the limit to reach those bonuses, unlike with 35+ contracts where you can just have games played (Jagr's contract with NJ for example).
Very good points about performance bonus $$.
"A" Bonus money of up to $850,000 is pretty flexible, highly negotiable, and attainable depending upon your agent and negotiating position. "B" Bonus money up to $2M is off the table unless you are good enough to win a major award ala Huberdeau for the Calder. The team and the league contribute to this bonus.
The $850,000 used to be available to only top 5 overall picks, but I think it is regularly included in just about any college graduate who is in a strong enough position to command it based on their college performance. I don't think you need to play a whole year to reach minimums for certain performance bonus' to kick in. Goals, assists, ice time, plus/minus and other performance based achievements can be low, high, or somewhere in between, although it is common sense that you need the ice time to achieve these milestones.
In any case, you are correct that the overall bonus picture is skewed to reflect a greater disparity than actually exists, but it still doesn't detract from the fact that you can have two or three hundred thousand difference in annual salary and close to $750,000 in "A" bonus money that is attainable if that player is given the opportunity at the NHL level.