NHL Salary Cap: How much should teams commit to their star players?
This article is a smart way to look at it. It's not necessarily the cap hit, but the percentage of cap space your stars are taking up.
You could probably make a nice bell graph in regards to the first chart, with each teams success versus the collective cap hit of their 5 biggest contracts.
The cap space taken up by those 5 biggest contracts by previous Cup winners in the salary cap era is roughly between 45-50% -- which makes a lot sense, half dedicated to your stars, half dedicated to your secondary scoring & role players.
So if the cap is at it's projected $75million in $2015-2016, and Chicago doesn't trade away everybody else (likely just Sharp) - Kane, Toews + Crawford/Keith/Seabrook/Hossa/whichever 5 of the big contracts you choose is a little under $39 million or ~51% of the cap.
So it's really just about on target of where an elite team should be with their top tier talent.