With aerodynamics playing a big role in handling, should we expect to see things like flaps or panels to help slow ships, as opposed to just things like the space brake?

Well, in the atmosphere, yes, right? Essentially, if you're going forward a lot, let's say you fly a Gladius, and you just really harshly pull up and expose the whole surface of the ship against the wind, you will slow down a lot. So, yes.