In a roundabout way they have mentioned consequences to actions in the past.
However, I think that Hunter is so focused on saving his family that he's throwing caution to the wind.
But he probably is trying to minimize any time disruptions so that he can calculate a way to stop Savage without inadvertently bringing about an even worse future.
As long as the time changes are done in a controlled way, he may be able to stifle any ripples caused.
The problems would come more from accidental time changes that aren't caught fast enough.
Of course, I think that once Savage is defeated, their actions may leave them bouncing through time doing damage control for the series' duration.