I totally get how you feel, I used to feel exactly the same way. I still like all those things about Kadri but I would only be upset by a trade if we didn't get good value back for several reasons:
He has 3 years left on his contract, still attractive but not nearly as attractive as it will be next summer when he only has two years left and his value will keep declining as we get closer to the end of that contract.
He's maybe not as important to the team as he was a year ago because of his reduced role.
If we can't count on him to be available when it counts the most, perhaps we need a new "heart" anyway.
He's at that age where you start thinking about a decline anyway. Does it start happening this year, next year, 2-3 years from now or has it started already? This is always a consideration and if we trade him just before the decline kicks in then that's obviously a good thing.
I'm not one of those people that hates him or says we have to trade him. I can see good reasons to consider it though more than ever before, I'm more open to it than ever before and if we don't trade him, I know I'll be very afraid of how he behaves in the playoffs next spring, especially if we face Boston again (seems likely). All I can say is if we do keep him, we better take all the steps we can to prevent a repeat suspension and I ask the same questions I've asked before - did we take these steps during the last 12 months, if not then why not and if we did, then how can we possibly count on them working now when they didn't work before?
As much as I love the guy and have also thought of him as the heart of the team, I also know that no one player is critical to success and if he leaves, there absolutely will be life after Kadri.