Making Co-op fun for everyone

Recommend giving each additional player in the campaign their own commander. Letting each player customize their own commander that joins the co-op will greatly increase the replay value of the co-op campaign and provide more things to do to additional players. If challenge and difficulty is an issue I recommend adding a separate co-op campaign tracking similar to halo how co-op wins only count for co-op and not single player if people want to beat the campaign by themselves and let everyone know how hard they had it.

That would be amazing! bring a lot of replayability to the campaign in my opinion. How difficult would it be to implement I don't know much about development?

If two people play the whole coop game together, do they get two commanders throughout? Is one level 1 while the other levels with the campaign, since only one player is the host?
A) Easiest I would think would be both commanders are locked to the same level as the host commander that way both level together and can come up with some interesting comps

B) If you want to get real fun can have the commander level be tied to every campaign mission he plays allowing the commander to level up beyond the current max level potentialy

C) Commander level tied to the players campaing


How does this system interact with people who have independent singleplayer campaigns, and play coop sometimes? Currently the campaign essentially copies saves from the host into a new save game. There may need to be a player choice in a new system, which requires some UI design.
A) Player choice is usually good I agree

I imagine if someone doesn't want an extra commander then they can play solo?