Well if he makes us better as you said, and if we're just a "a playoff team" added to that we have reclamation projects like Tyler Ennis playing with our best player then we kind of do need him. He's a 60-70 point player now with the potential to score even more. Let's not pretend that's easily replaceable. That's not even getting into other things he does well zone entries, takeaways, PP etc...
I'm not saying give the $8M that he's rumoured to be asking for, but there's a middle ground here and both sides would be well served to get there when talking about a long term deal.