I like the idea a lot! However, I have two qualms with it.
One is depending on the business model they decide to go with it, it could turn out very differently. If they make it F2P content but then put in paywalls, I'd be dissapointed. If they just made it a standalone piece of DLC, I am all for it, but if it unlocks weapons or items you can't get anywhere else, that's blatant pay to win. (If its cosmetics, HUD items, skins, taunts, etc only that would be fine, as they have no impact on gameplay). If they made it free content with purchasable cosmetics and in-game unlocks, then that leads me to my second qualm.
Which is I'm not sure the amount of time, money, and man-hours it would take into developing this would be worth the return in increasing the playerbase (for a long-term increase), and revenue received. That especially would worry me when realizing something like this would take away from development on the main game. However, depending on the business model and way its marketed/provided, it could be a great addition.
Ignoring EVERYTHING else, I WOULD ABSOLUTELY LOVE A COOP CAMPAIGN! Gives me Steel Battalion fuzzies in my gut just thinking about it. :D
Edited by Seron16, 15 April 2015 - 03:21 PM.
KOBALT DEFENCE REGIMENT
...and let slip the dogs of war...