I wouldn't call iOD and Cluster Grenades to count for "pretty well equipped". iOD does not give the HoF an advantage. It would simply be a choice, whether to take the hit or iOD. I have fought against HoFs a number of times, and annoyed them enough to get them, to keep iODing upwards for the height advantage. By the time, they actually gain height, they have lost enough amount of health for me, to finish them off.
The Cluster Grenade is only powerful when it hits the enemy on the ground, you cannot mid-air cluster the person. And how many times have you actually dueled a HoF on even ground? There are plenty of places in every base, for an enemy to get above, and render the cluster useless. Not only that, but if you're not at a good height from the plane and shoot the grenade, it will just bounce up and explode, releasing the clusters in all directions.