There of course are many issues. But the contract length is one of them. Right now you can sign your OWN players to 7 years and players from another team to 6 years. I think the Owners want to bump it down to 5 years for their own players and 4 for players from another team. I think there is a good chance this will get done.
The minimum age issue will also be big; Stern wants the age limit, but the players don't want it at all.