Topic does exactly what it says on the tin. Let's start with characters...
The 2e base game characters are included in the set, as are some from other 2e expansions. In some places there are minor differences, but apart from the Minstrel (who is a relatively weak character anyway) losing his immunity to the Hag, I don't think there's much to complain about here.
Talisman the Expansion has fared pretty well. We're still waiting for Barbarian, Halfling, Hobgoblin, Pilgrim, Ranger and Satyr. Additionally the Rogue character from 2e was significantly different from the one described in 4e (more like a Thief for Spells), so there's some functional space for a new character loosely based on the 2e Rogue. The Pilgrim's convert ability is a little similar to the Ogre Chieftains dominate ability, although his Exorcise ability is quite unique. In 3e the Barbarian had a Beserk ability (optional, chosen before combat: +2 but if you lose you lose 2 lives), in 2e he was able to attack twice provided he didn't take a life in the first battle. Of the two I think I prefer the 3e version. The satyr's Panic needs to be worded so that it can't be used in the Inner Region or CoC and his grab followers within three spaces, is too low risk for my liking, but that's a matter of perrsonal taste I guess.
Talisman The Adventure was my favourite set, with significantly more complex cards than most other sets. So far, the only character which has survived is the Warrior of Chaos, which has been transformed into the Dark Cultist - he has lost his corrupt ability (which was a pain in the neck anyway) and the general consensus on these forums seems to be that the Rewards ability is now too good. Maybe there should be a house rule that the Cultist only gains Rewards from attacking Good characters or can gamble their experience stack for rewards - e.g. discard trophy, roll a dice, if it's less than the Str / Craft of that enemy gain a reward - but I'm digressing.
Of the cards that didn't make it we have the Centaur, Ninja, Orc, Samurai, Soldier, Witch Doctor and Woodsman. The Cenatur and Woodsman seem likely to appear in the Forst expansion. The Soldier would probably make a good candidate for the City Expansion. If the Witchdoctor survives the cull, his Evil Eye (which forces players to visit the Ruins / Chapel) seems unlikely to make it, as it adds an unnecessary level of bookkeeping to the game. The Samurai and Ninja represent "real world" cultures - so far we only have the Amazon on that front, and Amazons are a fairly staple trope in fantasy anayway. The Ninja also has a lot of disadvantages - and characters with disadvantages aren't always that fun to play, however cool Ninjas are. The bow which is possessed by both the Samurai and the Cenatur is also problematic. Ranged weapons never really worked in Talisman IMO - which might explain why we haven't seen the Archer yet. The Orc fits much the same functional and flavour space as the Hobgoblin - I suspect that if we if we get the Hobgoblin we won't see the Orc and vice versa.
From the Dungeon gave us we are still "waiting for": Conjurer, Inquisitor, Martial Artist, Pirate, Saracen, Scout, Spy, Swordsman and Zulu. Technically we also looking for the Dark Elf but he's so similar to the Vampiress, that it's not worth bothering with. With the correct spell (Finger of Death) the Conjurer could be devastating. If he returns, expect his discard a spell instead of the one you are casting capability to be toned down siginificantly. The Inqusitor "imprison" ability is a little like the Evil Eye of the Wicth Doctor in that it disrupts the flow of the game. It also makes less sense with the Dragon Raid (dragons expansion, Destroys the Castle) and the Jail within the City. Saracen and Zulu are real world cultures again, although Saracen fairly closely corresponds to the 3e Dark Elf from White Dwarf.
Spy and Scout having their "hiding" ability - interesting power, but turns portions of the board into dead squares for other players. Pirate is fun - removing Strangers from the board. If his ship docks at the Wharf instead of the Woods, he could make it into the City. Swordsman isn't especially unbalanced, so seems like a shoe-in for pretty much any small box expansion. The Martial Artist occupies the same flavour space as the Monk's inner belief implies. It's possible that a combination of the Ninja and Martial Artist might make a workable character - The 3e Assassin seems like a combination of these two.
It's seems unlikely that we will ever get the Timescape. It never real "felt" very talisman anyway. Therefore the characters: Archaeologist, Astronaut, Astropath, Chainsaw Warrior, Cyborg, Scientist, Space Marine and Space Pirate are unlikely to see play in 4e. Theoretically we may seem slightly reformed versions of some of these characters - the Scientist could become the Acaedmic, the Archaeologist could become a Tomb Raider, Explorer or Graverobber. Some of their abilities could appear elsewhere - the illusions from the Astropath might appear on an illusionist character, for instance.
The City gave us 4 Master Level characters - we'll have to wait to see how FFG handles the City before we pass judgement on them, though my preference is for the more scaled down versions found in 3e. The promotional material for the city that appeared in 3e also gave us four more ML characters - again, we will want to wait until we get the FFG city before turning our attentions to these characters. The city also supplied us with the Valkyrie (now available in 4e) and the Minotaur - a strong character that lacks a killer ability. Immunity to the Maze, Crags and Siren plus inability to wear a helmet. Maybe he should inherit the Great Strength ability from the Chaos Dwarf in 4e (when you attack another player, they cannot use Armour to prevent loss of life)
Dragons furnished us with 4 characters who strengths were closely linked to the Dragon theme of the set. Dragon Priest, Dragon Rider, Questing Knight and Dragon Slayer. Two of these characters (Dragon Rider and Dragon Slayer) transferred to 3e. The Questing Knight was awful. His starting equipment (Sword, Armour, Shield and Helmet) was superfluous - you only get one armour saving throw. His inability to attack weaker monsters meant that a lot fo cheap experience went amiss. The Dragon Priest is mostly tied to key cards within the set. This means he can suffer from deck dilution if you play wiht every expansion. Dragon Rider was reasonable - perhaps a little underpowered, especially if there are few dragons available. The Dragon Slayer had numerous disadvantages - he couldn't evade Dragons, had to go mad when fighting a Dragon (roll two dice, but if you get a double you lose one life in addition to the outcome of the combat) and he couldn't use any armour except for a shield. If his berserk rage was optional and he got a bonus fom killing dragons (e.g. +1 fate) he might make a better character. My suspicion is that if we see any of these cards is likely to be in either a Dragon themed small box-set or as part of the Dragons Towers.
The 3e sets were mostly rehashes of 2e, with many unqiue abilities lost - making many characters a little bland - and some capabilities assigned to new characters. many of the names are propietary (e.g. Skaven), so we may not see the exact characters again, though we may see a few of their abilities: The Witch Elf had poisoned weapons (causes loss of two life when you take a life from a character) This strikes me as very strong, especially in conjunction with Finger of Death. The Chaos Dwarf had Great Strength - which I'd suggest should be used on the Minotaur to make him a little less bland.
Two characters seem relatively distinct: The Goblin Fanatic and the Fire Wizard. - The Goblin Fanatic had a similar two dice combat attack to the Dragon Slayer; roll a double and you auto-lose the combat. His starting stats were weak: S=3, C=2, couldn't use Weapons, but he wasn't forced to roll both dice and if he got a double he'd only auto-lose as opposed to lose one life and then lose another when the dragon beats you! The Fire Wizard began with Fireball and, whilst he couldn't cast it more than once per turn he didn't have discard it when he cast it. These characters could easily be remodelled to Fanatic and Pyromancer respectively.