Supposedly the NHLPA fought hard to keep the rules the way they are. I think a reasonable change that they might accept is letting the team with the player's rights offer a better contract than what they'd get as a UFA (similar to NHL UFAs now). So either a longer term or more money. That way there's extra incentive for the player to sign with the team that drafted them (or traded for their rights) but the team would have to lean in too, and players could still opt to go their own way.
How about a compensatory draft pick equal to the value of contract signed? Most ELCs are slotted/paid based upon the players draft position, but teams can pay more. Lets take Borgen for example. He was a 4th rd pick, but if someone signs him to a deal with 1st rd money, we’d get at least a 2nd rd pick as compensation. This can be done with by the NHL giving us a pick at the end of the 2nd rd or better yet, just like a team signing a player to an offer sheet, we’d get their 2nd rd pick.