The concept of Open Play is to create an element of player and player interaction, whether that is Player vs. Player or Player with Player. While we don't have all the information about Wings yet there are a couple of things that have already been said during newsletters. One of the things they have said is that they do not favor fleet based super cruise or player turn over controlling (aka like Eve where one player warps the whole group). Hence it won't be any easier/harder to fly as a group in super cruise than it is now. Its also been stated that there won't be any form of "follow" mechanic, the devs seemed to agree that this would be bad for the game.
What hopefully will be the case is that we will have better indicators and feedback in terms of where members of your groups are and ways to find them in space and fly to them through the interface.
The most important thing that Wings needs to bring are team driven cooperation. Shared bounties, shared missions/mission rewards, shared consequences and responsibilities, share faction increased, shared scans/maps hopefully, better instance grouping, better communication between players, information about each others status (perhaps a group panel that shows fellow group members shields/hull for example).
Now as far as the whole 4 on 1 (group advantage), these are things that belong in the game. They may not be fair, but you can't have your cake and eat it to. Either your playing an online game (open play) and you live with the benefits and drawbacks of it, or you play solo or group instance and avoid it. I think what a lot of players want to do is force some form of morality onto online play which I think is wrong. What we need are reasonable and logical mechanics in response. Players should have the means to be pirates and outlaws if they like. There are consequences for their actions already and they are good ones.
If there is one thing I would suggest is that we make it possible to send out distress calls that appear in super cruise drawing your attention to them. This way both victims have a way to call for help, bounty hunters can respond to help while pirates can use the mechanic to set traps (fake distress call). Most importantly though Distress Calls draw your attention to where players are, which I think is key as this allows as to find places of activity.