The original list is pretty good, though I'd switch an album here and there (e.g. Wolfheart instead of Irreligious for Moonspell, Cuelty and the Beast for Cradle of Filth, debut for Sirenia etc).
The list I'd make though would depend A LOT on how strict we go about defining gothic metal - e.g. do we include gothic doom metal and gothic black metal etc, or just the "pure" gothic metal.
And even then we have 2 options - the one that's an "intelligent" kind of metal rooted in western classical music (stuff like Estatic Fear "A Sombre Dance"), and a heavier sounding gothic rock (e.g. Type'o'Negative). Though most of the bands combine those things in various proportions (heck, even Paradise Lost at their supposedly doom metal albums like Gothic had tracks like Shattered, Eternal that with some adjustments to the sound could be made very close to Sisters of Mercy stuff - though one would be hard-pressed to say PL wasn't metal enough back then).
So let me try to do kinda 2 lists - the more "pure gothic metal" (which is impossible to get right, I guess) and the more "gothic metal and around" stuff like most of the lists above.
So, for that "pure gothic metal":
1. Silentium "Altum" - underrated band, early releases up to Sufferion (including) are a great example of gothic metal, with some more doom influences at demos (Illacrimo and Camene Misera - great ones... if you manage to find them) - as it used to be for many others.
2. On Thorns I Lay "Crystal Tears" - absolute gem of an album that is made to be such by the use of Viola. It's kinda similar to Aegis in a way, though very different at the same time. Criminally underrated.
3. Theatre of Tragedy "Aegis" - need I say more?
4. Avrigus "A Secret Kingdom" - Amazing album from a relatively unknown band. A little bit short (if you exclude all the ambient intros and interludes), but very diverse - though consistent as an album. Great stuff.
5. Enslavement of Beauty "Traces o' Red" - this one comes from sort of a melodic black/death/heavy metal area, but it's definitely not black or death or heavy metal itself, unique stuff, and surprisingly almost no gothic rock influences (unlike subsequent albums), the guitar moves are much closer to some "neoclassic" stuff. Very unique in general and also very little known, I think. So again, criminally underrated.
6. To Cast a Shadow "All Alone" - just a very solid well-made album that fits the genre.
7. Funeral "In Fields of Pestilent Grief" - interestingly sounding more doom-rooted originally (with their brilliant "Tragedies"), but definitely into gothic metal area on this release.
8. The Hourglass "Through Darkness and Light" - the vocalist is on par with Tarja Turunen, but the music is more gothic metal with less pop or goth rock influences than say "Angels fall first" or "Wishmaster", and no power metal unlike "Oceanborn".
9. Madrigal "I Die, You Soar" - rather little known album, but a good one, with less "gothic metal" cliches like soprano female vocals, or gothic rock ones - like typical 1 and 3 beat and deep(ish) male vocals.
10. Lacrimas Profundere "Memorandum" - used to be pretty well known back in the day, worthy of bringing back now.
11. Estatic Fear "A Sombre Dance" - a classic. Not as good as "Somnium Obmutum", but that one was more a gothic doom album genre-wise. This one is a pure gothic metal to be, the one with western classical music base and without the gothic rock influences. It's 11-th, but it deserves a mention.
For the gothic influenced stuff that isn't "pure gothic metal":
1. My Dying Bride "The Angel and the Dark River" - a classic
2. Paradise Lost "Draconian Times" - same
3. Rotting Christ "Sleep of the Angels" - some angry reviewer complained it was too close to Sisters of Mercy or something, but that's the whole point!
4. Theatre of Tragedy "Theatre of Tragedy" - this album was overshadowed by the popularity of the two others that came after. But I would argue that "Theatre of Tragedy" is on par with "Velvet Darkness they Fear", and "Aegis" was already a different kind of music.
5. Trail of Tears "A New Dimension of Might" - heavy as f,
6. Tristania "Beyond the Veil" - a classic that needs not much intros. Shifted more into melodic death metal meets gothic metal rather than doom-rooted debut (which is also a great album though).
7. Moonspell "Wolfheart" - another classic that doesn't need much introducing. Tracks like Trebraruna or Alma Mater are probably not exactly Gothic Metal, but the rest fits the definition just perfect. Midnight rides, vampires and some erotic alchemy - what more can one ask for?
8. Sadness "Danteferno" - not a happy listen, but a great album. And "Aphrodite's thorns" is in a genre of it's own.
9. Artrosis "W Imie Nocy" - polish competitors to Theatre of Tragedy. This is probably their best release.
10. Darzamat "In the Opium of Black Veil" - amazing though short EP (which is it's only downside), rooted in symphoblack. It's a pity the band has changed direction since then.
11. Draconian "Where Lovers Mourn" - a classic. Period.
12. Ava Inferi "Burdens" - also a classic. Very nice atmosphere and unique sound.
13. Mystic Circle "The Great Beast" - honorary mention. Other albums by this band don't sound interesting to me at all TBH. But this one... it is just perfect in it's sound. It is like Dark Tranquility "Haven" merged with gothic metal (remember when DT got that groove metal influence, slowed down, had lower vocals, punchier though simpler songs/riffs? Yeah, I love that album - and this is that plus gothic metal, though probably with weaker songwriting).