Here's a revised list of general changes, arranged alphabetically. For ease of reading, I've removed the quotes from the discussions about those changes, instead supplying links to the relevant threads. One thing I realized as I was doing this is that we never actually came to a decision about the name 'Gwarestrin'.
{Amon Gwareth}[Amon Gwared] per LQ2 (HoMe XI)
{Amras}[Amros] per
Shibboleth and
Ros. Discussed in
Name Changes?
{Angamandi}[Angband] per
Q30.
{Artanaro}[Ereinion] per the ‘Shibboleth’. Discussed in this thread.
{Artanor}[Doriath] per
Q30.
{Auredhir}[Eluréd and Elurín] per
QS77
{Avranc}[Daruin] per
WH note 55.
{Bad Uthwen}[Way of Escape], decided in
Bad Uthwen vote after discussion
here
Battle of Sudden {Fire}[Flame] per
QS77
{Bansil}[Belthil] per
QS77
{Belthil}[Silpion] when it refers to the tree in Valinor, per
QS77.
{Bëor}[Bregor] when referring to the Father of Barahir per HoME XI
{Bladorion}[Ard-galen] per HoME XI
{Bronweg}[Voronwë] per
QS77and late 'Tuor'
{Celegorn}[Celegorm] per
QS77
{Celon}[Limhir] per 'Of Maeglin'
{Côr} [Túna] or [Tirion] per
QS77. In BoLT Kor corresponds to both the later Tirion and Túna, being the name of both the City and the hill on which it stands. It should be changed to 'Tirion' when it refers to the city and 'Tuna' when it refers to the hill.
{Cranthir}[Caranthir]
{Cranthor}[Caranthir] per
QS77
{Crisaegrim}[Crissaegrim] per
QS77
{Cristhorn}[Cirith Thoronath] per
QS77
{Cûm an-Idrisaith}[Cûm-nan-Arasaith] (Mound of Avarice) per
Q30. This may need linguistic revision.
Dagor {Vreged-sir}[Bragollach] per
QS77
{Dairon}[Daeron] per
QS77
{Damrod}[Amrod] per
QS77.
{Díriel}[Amros] per
Shibboleth and
Ros
{Dorlas}[Darlas] per
WH note 55.
{Dorlomin}[Dor-Lómin] for consistency with UT and
QS77
{Dor-na-Fauglith}[Dor-nu-Fauglith] per
QS77
{dragon-helm}[Dragon-helm] just for consistency.
{dwarfen}[dwarven] per Tolkiens general use of the old plural when refering to Dwarves.
{Eärendel}[Eärendil] per
QS77and LR.
{Egnor}[Aegnor] per
QS77 (except where it refers to Beren's father)
{Egnor}[Barahir] per
QS77 when it refers to Beren’s father.
{Elfinesse}[Elvenesse] per Tolkien's general change of Elfin to Elven from earlier to later writings.
{Erchamion}[Erchamon] per ‘Eldarin Hands, Fingers, and Numerals’. Decided in this thread.
Ereinion: No change.
{Ermabwed}[Erchamon] per ‘Eldarin Hands, Fingers, and Numerals’.
{Finellach}[Ereinion] per the ‘Shibboleth’. Discussed in this thread.
{Finrod}[Finarfin] per
QS77 when it refers to Felagund's father.
{Flinding go-Fuilin}[Gwindor, Guilin’s son] this seems to be covered by the two entries 'Flinding' and 'Fuilin' but since in alliterative verse Flinding and Fuilin are both in the alliteration it is here surely necessary to change the alliteration.
{Flinding}[Gwindor] per
QS77 but this change does only occur in the verse and Flinding is often used in the alliteration. Thus each line needs some special solution.
{Fuilin}[Guilin] per
QS77 but this change does only occur in the verse and Fuilin is often used in the alliteration. Thus each line needs some special solution.
{Galion}[Galdor] per HoME XI
{Galweg}[Orodreth] per
QS77.
{Gar Ainion}[Place of the Ainur], decided
here
{Gar Thurian}[Gar Thoren] per 'Etymologies': under 3AR-, section GARAT-. Decided
here
{Gelion} and {River Gelion} [Duin Daer] per 'Of Maeglin'.
{Gelmir}[Faramir] when referring to the companion of Arminas, per Narn plot synopses. Discussed in this thread.
{Glingal}[Laurelin] when it refers to the tree in Valinor per
QS77
{Glingol}[Glingal] per
QS77.
{Glommweaver}[Ungoliant] and {Ungoliantë}[Ungoliant] per
QS77
{Glorund}[Glaurung] per Wanderings of Húrin.
{Gnome}[Elf] or [Noldo] and {Gnomes}[Elves] or [Noldor]. “Gnomes” was dropped by Tolkien in LR and later writings, often replaced by Noldor. It would be better artistically to retain the original variation Gnome/Gnomes and Noldo/Noldli which can be best done by replacing Gnome/Gnomes by Elf/Elves except where a general reference to Elves would not fit, as in “the Gnomes were exiles at heart, haunted with a desire for their ancient home that faded not.” Then use Noldor.
{Gochressiel} [Crissaegrim] per
QS77
{Gondothlim}[Gondolindrim] per
QS77
{Gondothlimbar}[Gondothrimbar] per 'Etymologies'; under GOND-. Discussed
here
{Gods}[Valar] Tolkien almost entirely drops "Gods" as a English translation in later writings.
{Gorthu}[Sauron] or [Gorthaur] per LR.
{Gumlin}[Galdor] per HoME XI
Gwarestrin:
{Gwendelin} [Melian] per
QS77.
{Gwenniel}[Melian] per
Q30.
{Gyrth-I-Guinar}[Dor Firn-i-Guinar] per
QS77
{Haladin}[Halethrim] when referring to the general populace of Haleth’s people, per ‘The Wanderings of Hurin’.
{Haleth}[Halmir] when it refers to Haleth the Hunter per
LQ
{Haud-in-Nengin}[Haudh-en-Nirnaeth] per
QS77
{Hisilómë}[Hithlum] per S.
{House of the Swan}[House of Hador] when it refers to Tuor’s ancestry. The sign of Annael remains the Swan.
{Hundar}[Haldir] per
LQ when it refers to Halmir's son.
{Hundor}[Haldir] per
LQ.
{i•Guilwarthon}[Dor Firn-i-Guinar] per
QS77.
{Ing}[Ingwë] per
QS77
{Inglor}[Finrod] or [Felagund] per
LR
{Inwe}[Ingwë] per
QS77
{Indrafangs}[dwarves of Belegost] when not referring to the dwarves of Moria per
QS77
{Isfin}[Aredhel] per
QS77
{Karkaras} (Knife-fang)}[Carcharoth ('the Red Maw')] per
QS77.
{Kôr} [Túna] or [Tirion] per
QS77. In BoLT Kor corresponds to both the later Tirion and Túna, being the name of both the City and the hill on which it stands. It should be changed to 'Tirion' when it refers to the city and 'Tuna' when it refers to the hill.
{Lalaith}[Lalaeth] per genealogical tables associated with LQ2. Discussed in this thread.
{Legolas Greenleaf}[Laegolas], discussed
here and decided
here.
{Lhandroval}[Landroval] per LR
{Lothengriol}[Loth-a-ladwen] per 'The Lay of the Fall of Gondolin' (in 'Poems Early Abandoned, HoMe III).
{Lothlim}[Lothrim] This latter is the probable correct Sindarin form.
Maglor: No change. Discussed in this thread.
{Mahtan}[Sarmo] per
Shibboleth, discussed in
Name Changes?[/url]
{Maidros} [Maedros] per the ‘Shibboleth’. Discussed in this thread.
{Malkarauki}[Valaraukar] per Valaquenta published with
QS77.
{Mavwin}[Morwen] per
QS77.
{Meglin}[Maeglin] per
QS77.
{Melko}[Morgoth] per
QS77. After BoLT Tolkien almost never uses Melkor in narration of events following Fëanor’s invention of the name Morgoth, except in a back-reference to ancient times.
{Minnastirith}[Minas Tirith] per
QS77
{Nan-Tathrin}[Nan-Tathren] per
QS77
{Nauglafring}[Nauglamír] per
QS77.
{Nauglath}[dwarves of Nogrod] or [Naugrim] per
QS77
{Nienóri}[Nienor] per UT.
{Noldoli}[Noldor] per
QS77. Noldoli, though possibly still a valid form, is not used at all in
QS77or late Tolkien writings.
{Noldorin}[Sindarin] per HoME XI
Nost-na-Lothion: No change. Discussed
here
{Nivrost}[Nevrast] per
QS77.
{Palúrien}[Kementári] per LQ2 and Valaquenta.
{Peleg}[Huor] per
QS77and “Tuor and His Coming to Gondolin”.
{Pengolodh}[Pengoloð] per ‘Eldarin Hands, Fingers, and Numerals’. Discussed in this thread.
{Place of the Gods}[Place of the Ainur], decided
here
{Rodnor}[Ereinion] per the ‘Shibboleth’. Discussed in this thread.
{Rodothlim}[Elves of Nargothrond] per
QS77.
{Saeros}[Orgol] per
CoH
{Salgant}[Talagand] per “The Eytmologies”, decided
here
{Sorontur}[Sorontar] per “The Etymologies” (under THOR-, THORON-) and “The Wanderings of Húrin” in The War of the Jewels (HoME 11).
{Sarn Athrad} and {Sarnathrod}[Athrad Daer] per 'Of Maeglin'.
{Silver Bowl}[Dimrost] per
QS77.
{Tarin Austa}[Gates of Summer], decided
here
{Taur-na-Fuin}[Taur-nu-Fuin] per
QS77
{Tauros}[Tauron] per
LQ
{Tavros} [Tauron] per
LQ
{Teiglin}[Taeglin] per WH note 55.
{Tengwethil}[Taniquetil] per
QS77
{Thargelion}[Talath Rhúnen] or [Dor-Caranthir] per HoME XI
{Thingódhel}[Pengoloð] per ‘Eldarin Hands, Fingers, and Numerals’. Discussed in this thread.
{Thorn Sir}[Sîr Thoron], discussed
here and
here
{Thornhoth}[Thoronhoth] This latter is the probable correct Sindarin form.
{Throndor}[Thorondor] per
QS77and LR.
{Thu} [Sauron] or [Gorthaur] per LR.
{Tinwelint}[Thingol] per LR.
{Tower of Ingildon}[Tower of Nimras] per
QS77.
{Tumladin}[Tumladen] per
QS77.
{Tun}[Túna] per
QS77
{Umboth-Muilin}[Aelin-uial] per
QS77 and UT
{Úrin}[Húrin] per LR.
{Valmar}[Valimar] per LR
{Ylmir}[Ulmo] per
QS77