Hot take, but I wish the NHL went to shorter terms and lowered UFA age. Max 5 year extensions (if re-signing, 4 if UFA), and UFA age at 26.
This would drive a LOT of roster movement around the league and make for a more exciting, unpredictable product year to year.
The NHL as it stands now gets by on the strength of the sport alone. Most of the teams around the league are completely frozen by the hard cap, and it makes things boring as hell.
Either do something like a franchise tag, or reduce contract terms.