Myself would really love to see Thorin & co. in exile, wandering, maybe even that scene where Thranduil turns his back on the whole group, expanding as to why Thranduil chooses to so (as even in BOFA Thranduil DOES bring aid, and certainly re the book Thranduil has many unexplored qualities of character and motivations).

And the rebuilding in the Blue Mountains and more on the dwarves. So I think most, if not all of the dwarves could be filmed as is over the next few years. Lots of hair and dirt and prosthetics can help the fudging along, re "age regression".

Seriously though, has The Hobbit not done enough damage? It has already the achievement of the LotR films with its substandard writing, characters and excruciating dialogue, and completely misguided attempt to turn a children's fairy tale into a nine hour epic. Rather than do further harm to Tolkien's work, it's time for the franchise to end.

That would probs be the worst thing about a sequel (after the fact that it would be mostly fanfic) -- they would likely have to recast a lot of the characters, and for me, most of the original actors just are their characters.

As you said, the attempt to make Orli look younger in TH didn't work out very well. Still, the fact remains that he is a great Legolas, and I would miss him!

I always have doubts about sequels, and reboots, and even about favorite books being made into movies, but sometimes the result is amazing, so I would never automatically just say "no" to another Middle-earth film. The script would have to be pretty great, though, and I think that would be the hardest part.