The Heimdall is quite big (might just be my perspective) and has not the best powerplant. It is an agile gunboat, I will admit, but its fire arcs only point forward. It is plainly designed to kill fighters and bombers, as it has high turning and good dodging capabilities. I don't know how I'm going to turn the Tiger into a Rheinland Gunboat killer, as they seem superior in anti-cap combat.
The Ostwind, the Heimdall you've likely fought often, is designed to kill fighters and bombers. It can already have trouble at doing that already, as the Rheinland Bomber -can- get behind it.