I find simple is usually better with most fish. For example, last night grilled fresh cobia filets over charcoal basting with just butter seasoned with fresh chopped garlic, salt and pepper.
Wow is all I can say! I received some Cobia from a neighbor and immediately thought of your suggestion. I cut the fish into 1.5 inch thick pieces and fired up the grill. I put the fish on the grill for 6 minutes, brushed butter on it a few times, turned the fish and cooked for 5 more minutes. Again, brushing butter on while cooking. Wow is all I can say. Without a doubt, the best grilled fish I ever ate! again for the tip of keeping it simple!