A 60% triglyceride reduction is outstanding. That's on par with what fenofibrate achieves, and you did it through weight loss and metabolic improvement alone.
The HDL increase is also important context. HDL is notoriously hard to raise with medication — statins barely move it, and the drugs that do raise it (niacin, CETP inhibitors) haven't shown great outcomes. Weight loss and exercise are actually among the most effective ways to raise HDL, and an 18-point increase is at the higher end of what's achievable.
Were your baseline trigs of 298 fasting? That's borderline for hypertriglyceridemia diagnosis.