For the last few months, I have noticed for people are going into story mode operation more often than hard mode. This is simply because the rewards given by the hard mode is not the worth the time and effort.
To fix this I suggest that you implement hard mode into group finder the same way as the last two flashpoints, set a gear rating requirements, say 242 or 246, and if someone in your group doesn't have this Item Rating level then you can't queue for the operation.
As well, provide the group finder CXP reward but at a higher rate, maybe double of the story mode one, and provide a sizeable amount of unassembled components, hundreds, and/or a massive amount of credits, 500k or something around that figure.