Liam neeson should return for Aslan.
Besides that perhaps Peter Dinklage as Trumpkin and Ben Barnes with a small cameo in the end of Silver Chair.
Gary Sweet or Laura Bent didn't make much of an impression in VDT, since they hardly had any lines. Wouldn't mind them being recast. Their roles in Silver Chair are also minimal.
Eustace should be recast. We need someone younger 15 years at the most.

I wouldn't mind if Trumpkin is recast--his portrayal in movie!PC doesn't seem in continuity with book!SC, and I'm hoping for the scene when Eustace and Jill are introduced to Trumpkin.

On the other hand, I did like Gary Sweet as Drinian and Liam Neeson as Aslan, so if they could come back that would be nice.

It would be nice to see them come back, but the only one I really think should come back is Liam Neeson, and that's only if they aren't rebooting the series. I don't know if they'll do the short scene with Trumpkin. It isn't necessary to the plot all that much.
If Tilda Swinton came back, I would probably cry.

If only one cast member can come back I would really want Liam Neeson. He was perfect as Aslan. It would also be great if Dinklage and Barnes could come back too. I love it if Poulter could reprise too, but he's probably too old

Ben Barnes has no need at all to return, they can just hire an older actor to play Caspian.

I voted for Will Poulter (yes) and Liam Neeson. Many actors play teenagers when they are in their 20s (and even 30s); why not Will?

I will scream if Tilda Swinton goes near this production.

A strong yes on Neeson, Barnes, Dinklage, and Sweet (he's a great Drinian - a serious and loyal counselor). Also I did like Laura Brent is Lilliandil, I'd like her to have another chance, hopefully with a few better lines and less glow! But Will Poulter is just too old and tall to come back as Eustace, much as I hate to say so.

I get that you see the White Witch and the LotGK as separate characters, and to a certain extent I would agree with you. But it's pretty obvious that they're related in some way. If Swinton was cast, not as the White Witch II, but as the Lady of the Green Kirtle, played with a different style ( and different costumes and wigs and things ), but subtly referring to the same otherworldy power of the Witch, I think it could be an added benefit and not just a distraction.

I could almost agree with you, phfactor, if it weren't for the fact that the White Witch (and thus Swinton) has appeared in all three Narnia movies thus far! If she's in the fourth (which by now is viewed as practically a reboot) people will start to think she'll be in them all, like Aslan.

About Swinton, I'm not really actually set on her coming back, I'm just wondering why you all seem to dislike the idea so much. It is certain that she's an excellent actress, one of the best of her generation perhaps. She was an amazing White Witch, she really made that movie what it was through her performance. So what I don't understand is: why the violent threats of murder?

I get that you see the White Witch and the LotGK as separate characters, and to a certain extent I would agree with you. But it's pretty obvious that they're related in some way. If Swinton was cast, not as the White Witch II, but as the Lady of the Green Kirtle, played with a different style ( and different costumes and wigs and things ), but subtly referring to the same otherworldy power of the Witch, I think it could be an added benefit and not just a distraction.

If they would just take out the Lady of the Green Kirtle and switch in The White Witch in a Green Dress, yeah, that I would have a problem with.

Sorry, no.
The producers would never cast someone who had played such a strong and distinctive character in the first movie (plus little cameos in the next two) as a different character in the fourth movie.
"But the BBC did it that way," some people cry.
The BBC did it that way because someone in their production team thought it was a good idea to employ the same actress in all three of their serials, maybe because their own interpretation was that they were identical characters; the same actress played the White Witch in LWW, the Hag in PC, and the LOTGK in SC.
As a result a whole generation has grown up thinking they are probably the same person. But they are not.
Unfortunately someone who works for the book publisher wrote a foolish introduction explaining that the evil female is the same person in all of these books, which was printed in one or more editions of the books. It is to be hoped that they no longer have a job at Harper Collins.

It may interest you to know that for at least two years NarniaWeb had a ban on the topic of whether LOTGK was the same person as WW. The mods agreed (and ruled) that these were not the same, but one or two individuals refused to accept this, and made a big fuss.

I think I should clarify that I don't think WW and LotGK are the same, I just wouldn't be hugely concerned (relative to other issues) about Tilda playing both (as different characters) if it weren't for the amount of Swinton we've already been belabored with.

Adeona, I agree with your reasoning.
I love Tilda's work, but unless she can turn up as a tree or something it is not appropriate to recast her.

I voted for keeping Aslan, Caspian, Lillliandil, Drinian, and Trumpkin. I really do think Will Poulter will be to old. And the same goes for Tilda, even if I agreed with LotGK being the same as Jadis, which I don't. However age won't be a problem for the rest since they are supposed to be older. I know some actor's performances or appearance aren't quite what we super fans would like, but we've gotten used to them. If this movie actually happens I would want to look at the screen and be able to think "Oh there's Caspian!" There is a connection with actors and actresses we have already seen in a certain role that would be lacking if another, possibly even better, person took their place. Therefore I'm in favor of keeping all the familiar faces they can.

I voted for Barnes and Dinklage. I think think it would be great to see them in old man/dwarf makeup and add the the bittersweet of finding them old. I know I might be stoned for this blasphemy, but it wouldn't bother me if they recast Aslan. I think if that happens it would be for reasons other than a creative decision, but I wouldn't mind. Liam Neeson's voice has a excellent timbre and he certainly sounds the part, yet honestly his acting isn't so definitive that I can't imagine someone else taking over. As far as Sweet and Brent go, couldn't care less. I disliked their characters equally in The Voyage of the Dawn Treader though neither had to do with their acting. Laura Brent could return and if they removed her ditsy stuttering, made her look like a person instead of a glowing mannequin she would be fine. I don't really remember Gary Sweet much, but I think he could be fine too. I feel that recasting would be equally agreeable and, I'm assuming, cheaper.

Will Poulter was a lonely bright spot. I assume whoever is in charge of this decision will have to find that abstract balance between continuity and realism to determine if they want to retain him.

As for Tilda Swinton, I won't even dignify that with response....Okay, I lied. If they cast her as The Lady, I wouldn't even see the movie in theater, and not for boycotting reasons. I would assume that anyone who made that choice couldn't have produced a movie worth spending ten dollars and two hours in movie theater on. (Just to clarify, I think she made a great white witch, would have made a passable LotGK, though she is much too old. I'm objecting to the hypothetical melding of the witch characters)