Currently, Hawken is roughly similar to Battletech's Solaris setting, just plain Mech Arena Combat. Play a battle, get your results, earn some EXP, and that is it.
Yet, the opening video when the game boots up, shows a story, something to perhaps get pumped up for, but does not deliver on that. Why is that? This game has the potential to offer us way more than just a slightly different COD, but using Mechs for combat.
Why not take a queue from Activision's old PC game series Heavy Gear, which they had to scramble to get once they lost the Mechwarrior license.
One major point for Heavy Gear, was it had a "living world" game system, including maps, to show the actual live impact of each multiplayer battle played! The front lines would move, resources added or depleted (during raids or taking over supply camps), and new weapons gained. This was created way before Planetside, which also uses a living world campaign system. This gave a tremendous extra purpose for playing Heavy Gear. Each battle you participated in, had a real impact on that living world map, and your side/team. Not just another battle for EXP to gain a camo paint.
You already have that opening, emotional type storyline video when the game starts. Why not add it into the game? Add more purpose for playing, than just getting a new camo paint job. That might attract, and keep more players in the game. Just like in real world jobs, if the players/employees do not feel "engaged" in something, a purpose for them, they leave.
Just my thoughts, being one of the original Battletech boardgame testers (ages ago, when it was originally called Battle Droids), ran Renegade Legion demos at GamesCons for Sam Lewis (when he was at FASA), and helped Archon Kildare, head of House Steiner (as Morgan Hasek Davion) during the early days of Mechwarrior, when someone created the first ever Online Star Leagues campaign system to track multiplayer combat battles into a living world campaign system before anyone else did. So hope this might help. Thank you for your time.