Because I have to start somewhere.
Barbara Wright: Barbara comes from 'barbarian', wright obviously means someone who makes things.
hS's version: Uanuiel Tân. 'Uanuiel' is a cludge from uanui+iel, 'monstrous woman'. 'Tân' is 'Maker', and forms the second syllable of Cirdan's name. (Both taken straight from the Ardalambion wordlist.)
Ffwydriad's version: Edel Thavron. 'Edel' is purportedly Sindarin for 'stranger', but the source doesn't reference anything. This source gives 'Othol' as the Sindarin for 'stranger', and references PE17. This source gives 'Ethelion' as a translation of Peregrin (= wanderer), and I know Sindarin likes to alter the first vowel in words with endings, so 'Othol' or 'Othel' makes sense. A feminine name could be 'Etheliel', which might well contract to 'Ethiel'.
'Thavron' does indeed mean wright, and I feel silly for not looking it up directly. [Facepalm]
Best version: I'm gonna go with Ffwydriad here and give Ethiel Thavron as the best translation.
Ian Chesterton: Ian is the Scottish version of John, which comes from Hebrew 'Yochanan', meaning 'G*d is Gracious'. Chesterton I'm pretty sure goes back to Caster+Town, or 'Fort-Village'.
hS's version: Eruan Garthobel. I glossed Ian as Eruan, 'Gift of God', which... is wrong. [Facepalm] I'm on firmer ground with the surname Garthobel, which means Stronghold Enclosed-Dwelling - pretty much exactly the meaning in the original.
Ffwydriad's version: Eruainon Echadion. Eru we know. 'ainon'... the best I can do is this being Quenya for 'son of holiness'. The namelist gives 'Erufael', 'God is just', while the Parf Edhellen site gives 'raen' for 'sweet-faced' as its best approximation for 'gracious' (also from PE17). That would give 'Eruraen', which hurts to say. Maybe that's the source of Eruainon, with the R vanishing...
Echadion... hmm. 'Echad' for camp is sourced to Unfinished Tales, where it's part of a placename (Echad i Sedryn, Camp of the Faithful). Valid (I'm now irritated that Ardalambion doesn't give it; I may have to transfer alliegence to the Parf Edhellen.) Then you've got a 'son of' on the end, which isn't what the name means.
Best version: I think I have to go with the namelist + the accurate translation, and pick Erufael Garthobel here. Bonus points for the Doctor being able to call him 'Parthobel' and have it still be a word.
Susan Foreman: Susan means lily, by way of a Hebrew word which now means 'rose' as well, and an Egyptian one meaning 'lotus'. A foreman is a sort of practical manager: they stand between the people doing the actual work, and the management above.
hS's version: Elloth Taid. 'Elloth' is just 'flower', though it feels like it could mean 'star-blossom' - which describes a lily very nicely. We might actually want to go over to 'Meril' here, which literally means 'rose'. Taid is a word meaning second-in-command.
Ffwydriad's version: Elloth Hîrbenn. Elloth we know. Hîrbenn is a construct, Hîr+benn, 'lord-man'. 'benn' is actually an archaic word for husband, which has slipped over to just meaning man. In constructs it should actually show up as either 'ben' or 'ven', which suggests to me that we should avoid it. Instead, we can use the archaic word dîr, which shows up in names as -nir or -dir.
Of course, we can't exactly use 'Hirdir', so now we need another word for a mid-level leader. Hmm... how about taid? :D Taidnir works perfectly well as a spoken name, though I admit it looks a bit clunky. Failing that, 'Herdir' is a genuine Sindarin word for 'master', as used to mean 'Mister'. And the idea of the Doctor's junkyard being named 'Some Bloke's Yard' tickles me.
Best version: I just can't forsake the star-flower. Elloth Herdir it is.
hS
(PS: inb4 'Susan is the Master!'. Oops...)