Directive 7 is a tad harder.
Be careful with Directive 7. It has a real high bug rate that makes the boss unable to kill. With that in mind, the only two Hard Mode Flashpoints that are either broken to the point of no completion or just dang near impossible are Foundry and Directive 7. And while Boarding Party can be difficult (as it's a great DPS check on that final boss fight), it is more than doable. The other three FPoints are cake-walks by comparison.