Not to disregard your feelings because you can be disappointed for any reason, but to come back on this specific line : when they said "new plans for Deep Dungeon", it meant that they were actually planning on doing a new one. They stopped after HoH and Orthos was also tentative, so it was a way of saying that the format will continue on.
For the rest, well, Deep Dungeon will still be Deep Dungeon. If it was a wildly different progression, where you bring your actual gear from outside, might as well just be a new piece of content. No matter what, Deep Dungeon will always be a set number of floor, procedurally generated, where you level up and improve a weapon you can take outside after some time. Then again, if a new piece of content akin to Deep Dungeon but with these changes appeals to you, it's always good to voice that you want something like that !
For what makes it different, it is the setting of course, but also the mechanics have been quite improved, especially how this content deals with wipes for progression towards Floor 100. I think Votives are also added on top of regular floor effects, but someone might correct me on that.
And what really sets this one apart I think is the floor 99 boss and its instance. The fact that it is a boss whose difficulty is adjusted by player input is very interesting to me, and if it works out it could be a great idea to expand to other pieces of content.