I sometimes make this with canned tuna; and I sometimes poach or bake the halibut. I double the dressing. This works really well for guests, because it can be made ahead and served at room temperature. It's always a big hit!!
This was a nice salad and the dressing is pretty good. But the halibut doesn't really go with the salad very well and feels like an afterthought. I tried it with canned tuna too, and at that point it just seemed like a lot of work and a lot of ingredients for what it was.