My favorite is Conguest of the Longbow then Dark Seed then Kings Quest, I also liked space quest. police quest was nice also

The Gabriel Knight games have a great story, the third game is an early 3D game so it take a bit to adjust to it.

The Blackwell series is another good set of games I would recommend.

The Syberia games are also well done, they have a great world to get lost in, the third game is a bit rough though.

Did you also play Quest for Glory? If not, the series is available on GOG. If yes, and you liked them, you might also be interested in:

Mage's Initiation: Reign of the Elements
Hero-U: Rogue to Redemption
or Heroine's Quest: The Herald of Ragnarok (not on GOG, but free)

The Journey Down Trilogy, Unavowed, Primordia, Grim Fandango, Quest for Infamy.

Well... if you have the patience to browse the games section, you'll likely find some very nice games which you may find interesting. Take a look around and I bet you'll find plenty of cool stuff:
https://www.gog.com/games?search=Point-and-click&page=1&sort=release_asc

And since you like the old-school type of adventures, here are some personal suggestions, some of which you may have played already:
https://www.gog.com/game/quest_for_infamy
https://www.gog.com/game/order_of_the_thorne_the_kings_challenge
https://www.gog.com/game/legend_of_kyrandia
https://www.gog.com/game/inherit_the_earth
https://www.gog.com/game/simon_the_sorcerer

If you are in love with pixel art style, try out Point'n'Click Adventure games from Wadjet Eye Games Studio, they are well known for atmosphere and some cool interactive features in their games!

It’s not usually my genre, but Machinarium was fun, with a neat art style.

In addition to already mentioned: Interplay's Star Trek games, The Darkside Detective, Guard Duty.

The Quest for Glory series 1-4 and the Secret of Monkey Island (the first one) are my favorites.

Well, you seem to be rather into the Sierra style of adventure games, which I was never a fan of, but if it helps, here are some of my favorites:

Chains of Satinav and Memoria - two fantastic fantasy stories, with beautiful graphics and sensible puzzles. CoS might just be my favorite point & click of all time.

The Deponia series - 4 great, funny, silly games with nice, cartoon graphics. And, despite of the silliness, the puzzles almsot always make sense (although sometimes it's a very tricky, particular kind of "sense").

Indiana Jones and the Fate of Atlantis - really feels true to the movies, the graphics hold up, the voice acting is mostly solid. The only downside is that the last act of the game features some really tedious mazes and the puzzles get a bit annoying at that point. Still, well worth playing.

The Journey Down - tremendously fun adventure in a unique setting with super likeable characters, nice music and sensible puzzles. Good voice acting, lots of humor.

Day of the Tentacle Remastered - next to the Monkey Island games probably the best of LucasArts. Funny, unique, and with puzzles that make sense rather than driving you crazy (like, say, The Dig or Full Throttle)

1954 Alcatraz - very unfairly overlooked game in my opinion. Good puzzles, godd story, and a setting and style not like most point & clicks - it's neither a comedy, nor a super-serious grimdark thriller but rather a fun pulpy noir sort of thing.

Well, guess I'll be the first to suggest the Curse of Monkey Island.

It's easily the best of the Monkey Island series in terms of puzzles, humor, and design. It has a charming 2D had drawn style, and has aged quite well. And it even has a musical number!

Some great series that haven't been mentioned:

Broken Sword (especially 1, 2, and 5)
Monkey Island. (edit: OK mentioned above)
Beneath/Beyond a Steel Sky.

It's my favorite of the series as well, and one of my favorites of all time. I only didn't mention it because Monkey Island seems so obvious.

As a sidenote: I think to fully enjoy Curse it's best to play the first two games first. Not obligatory, but it helps.

Quest for Glory series and Grim Fandango are my favorites.

If you are into something more different (all events in-game occur in real time), I suggest The Last Express.

The Dig, The Longest Journey (I only played the first one), Monkey Island series, Beneath a Steel Sky (which, btw, is free) are also very well made and enjoyable.

Virtuaverse
Kathy Rain
State of Mind