Cool, I rekon support - the turret sounds cool. That's what I will go for when I play the Commando. I really don't think it will matter too much though - just go with whatever you think sounds best.
I am worried about us getting severe level gaps in this game. Maybe we should have a dedicated co-op character each, that we never level on our own to solve the level gap issue?
I found some useful info to be aware of in multiplayer on Borderlands:How does dropped loot and ammo work for co-op play in Borderlands 2?
Loot drops are not individualized. Don't be a hoarder! Ammo is shared. Pick it up! Grenades and Rockets are not shared.How does experience and money work for co-op in Borderlands 2?
All experience and money are shared.How do quest rewards work in co-op play? Do all players receive the same reward?
Reward items for completing quests are given to each player. So if a reward offers a shotgun, and only one player turns it in, everyone else will have a similar shotgun added to their inventory.How does quest progression work if the host player is further along than my character?
Lower level characters will automatically have their missions marked as completed during the session in which there is a vast level difference between players. You will keep currency, XP, and any loot you earned or picked up in the session, but the actual completion of the story mission must be done again in your single player game. Special note: When a player returns to their own game world they will be given the option to "Fast Forward" through any story missions they may have completed once they have progressed to the proper time in their own story line. How does game progress work?
Game progress is shared between all co-op characters in a session so long as each character has progressed to the current story mission. If guest players are on the same story mission as the host, story progress will be saved in the guests' and host's campaign. Story progress will not be saved for characters who have not yet reached the host's campaign mission. Basically, you can't skip missions by playing co-op. You can still participate in the mission and get experience and loot, but if you go back to your single player game - you'll still need to complete it again. The player with the least story progression should host the session, that way they won't miss out on any story elements. Do enemies scale based on the number of players?
Enemy levels are based on a number of factors including the area and host player level. When more players enter the game the enemies become more difficult. They also drop better loot!