Well, TCD, 5h00n4y and xpect, what is sure is that all games you mentioned were top notch adventure games I enjoyed - and still enjoy! - A LOT!
BASS is huge (again, I'm a SciFi fan ;D) and Gibbons' work is absolutely great.
IUC was a real good game, better than it's sequel Guilty imo, but I wouldn't put it on top of other games. It was good, without being absolutely unforgettable.
Goblins is a classic
And all Lucas games I've enjoyed. Every single one of them. Indy 3 & 4 are amongst my all-time favorites, DOTT...who could have missed DOTT? (Was it ever released on Amiga btw???) Loom was too short, but was unique with a very fantastic atmosphere, Sam n' Max, I've probably never laughed that much playing an adventure game (same question as DOTT, was it released on Amiga??), even The Dig was fabulous in my opinion (but probably the hardest puzzles I've seen in an adventure game despite a very basic interface!).
I'm probably forgetting a lot of games, but let's keep in mind that early Sierra classics were from another computer age
They did set a standard for future productions.
And I guess there's one thing we may all agree on: adventure is a genre that really died with modern computers...what a shame
I'm really missing the genre.