I actually rather like Hullbreaker HM :/ Then again I am biased because I love Lominsian lore.

The single hallway with tons of gates does not bother me at all. In fact I enjoy it since random healers (who often are not good at healing) wont pester me to do mega big pulls. I also like all the boss fights, even the first since it is unusual to have an entire fight be nothing but add waves. Certainly a break from a HP sponge that occasionally summons adds which the vast majority of dungeon bosses are.

However I would have liked to see more of the island. Still that is a minor complaint.