As we approach the end of the Lord of the Rings saga expansions, we've seen most of Tolkien's significant characters appear as player cards, and many of them as heroes. To avoid too many duplicate versions of characters, we've been seeing more FFG-created heroes: the Dreamchaser cycle was the first to have 3 FFG-created heroes, and there's a decent chance that we'll have three FFG-created heroes in the Haradrim cycle. Círdan is the only Tolkien-created hero in The Grey Havens + Dreamchaser cycle who hadn't appeared in the game before (although Galdor and Elfhelm hadn't appeared as heroes before), and I wouldn't be surprised if Hirgon is the only hero in The Sands of Harad + Haradrim cycle who's a Tolkien-created character new to the game. I thought this might be a good time to take stock of the Tolkien-created characters who haven't yet appeared as heroes, but have a decent chance of doing so.
Here's a list of characters who we haven't yet seen in the game and seem to me to have a decent chance of appearing as heroes (there are license problems for the Blue Wizards). I expect most of these characters to appear as either heroes or allies at some point:
Thranduil
Thorin Stonehelm
Bard son of Brand (could potentially appear with Thorin Stonehelm in a new saga expansion focused on the battles of Dale and Erebor, like the fan-created scenarios Matt Newman was designing before he joined FFG)
Grimbeorn the Old
Húrin the Tall
Bergil
Angbor the Fearless
Several other Outlands/Gondor possibilities; Duinhir or his sons Duilin and Derufin seem likeliest
Leaflock (one of the three oldest Ents, although he's described by Treebeard as "grown sleepy, almost tree-ish")
Paladin, Thain of the Shire
Farmer Cotton
Rosie Cotton
Here's a list of characters who have appeared only as allies, but I expect have a decent chance of appearing as heroes:
Quickbeam (perhaps in The Crossings of Poros)
Skinbark (seems likelier than Beechbone, as one of the three oldest Ents)
Saruman
Radagast
Gwaihir (likely in Mountain of Fire)
Gildor Inglorion
Rumil
Orophin
Bofur (less likely, since two ally versions)
Anborn (less likely, since two ally versions)
Forlong (probably without the Outlands trait)
Déorwine (stands out among the many Rohan allies as chief of Theoden's knights)
Gamling (also stands out for his commanding role at Helm's Deep)
Grimbold (also stands out; he was key in defending the Fords of Isen after Théodred fell, and led one of the first three companies in the battle of Pelennor Fields)
Ghân-buri-Ghân
Farmer Maggot
There are also characters who have appeared as heroes, but I think there's a good chance of getting another hero version of that character (these seem the most likely, but many others are possible):
Aragorn (so many people have requested Spirit Aragorn, and it would fit for Aragorn to be the one hero with versions in all four spheres)
Frodo Baggins
Sam Gamgee
Éomer (mentioned in the announcement article for Mountain of Fire; very likely to be a hero there)
Did I miss any likely hero candidates? Which Tolkien-created heroes are you most interested in seeing? Which heroes would you like to see appear in another sphere?