The NHL cap needs work. The creative accounting/ridiculous contract lengths especially need to go.
That said, the Hawks eeking into the playoffs and the presumed league-wide parity has a lot more to do with the point system than it does the salary cap. That is what really needs to change.
The 2010 Hawks won 8 more games than this year's squad. 8 games is substantial, but it's not that bad of a drop off all things considered. Losing 2 homers to Edmonton and dropping 3 to Colorado in the first 2.5 months of the year shouldn't overlooked. Chalk them up to whatever you want (hangover, new players acclimating, etc), but those are 5 games that are uncharacteristic losses for this team. Colorado and Edmonton are baaaaad teams.
My point is: despite a legitimately traumatic roster shake up in the off season (loss of depth, scoring, character/chemistry, etc), this years Hawks team isn't horrible even after getting hit harder by the cap than any team has (and likely ever will). You want a worst case scenario of a salary cap breaking up a great team- the 2011 Hawks are the shining example of that for years to come.
And yet, the 2011 Hawks still made the playoffs and are still a threat.