I think Hydra show be a terrorist group that believes that Democracy is
fundamentally flawed and weak system, concerned more with electing popular leaders, rather than effective ones and that it is unable to solve the world's problems. They believe the solution is overthrow all democracies and replace them with one world wide dictatorship that will take decisive action to end overpopulation, war, poverty, etc. Members include normal civilains,
captains of Industry, US sentaors, third world government officals, etc. In fact I think Fenrus and the Von Strucker twins should be involved with Hydra.
Their leader is Viper a deranged fanatic and psychopath who stop at nothing to achieve her goals. I think Viper is more interesting that old Nazi relic baron Wolfgang von Strucker and she could give the Ultimates a female foe.