If you managed to play through the Syberia games and Sanitarium without a walkthrough, you can't be that impatient and bad at solving puzzles. I think few adventure games have actually 'difficult' puzzles, it's more a matter of how well what they expect of you resonates with the player or not and that can depend on many factors, your experience with the genre, obviously, but also your way of thinking, your current mood etc. And many have design flaws but that doesn't necessarily make them difficult for everyone either.

Anyway, I would suggest Telltale adventures as more focused on storytelling than puzzles, if they hadn't been removed from GOG. The Blackwell series and Unavowed are rather light on puzzles and strong on story, too. Botanicula is another rather simple and easy one, as are the so called 'Walking Simulators' with light gameplay/puzzle elements like Oxenfree, Firewatch, What Remains of Edith Finch, or Jazzpunk.

If you like first person adventures, there are some easy like Return to Mysterious Island or Amerzone. Drácula saga is also quite easy.

The Book of Unwritten Tales.

All the Spiderweb Software games can be tweaked down to either Easy or Tourist.

Edit: Probably the wrong type of adventure.

Whatever you do, if someone suggests a Sierra game, ignore that suggestion.

Blackwell series.

I second the recommendations for the Blackwell series and Unavowed, those are comparatively easy, with a focus on the story.
Shardlight also isn't that hard imo.
I disagree with the recommendations of the Monkey Island games, the 2nd one especially has some extremely obscure puzzles.

I would recommend The Longest Journey and its sequels - Dreamfall:TLJ and Dreamfall: Chapters.
I've managed to beat them without walkthrough, unlike Syberia.

And I also join to people recommending Blackwell series. Note, that in the later Blackwell games there are even in-game hints - you just ask other character what to do if you stuck. Also add Gemini Rue - it's even easier than Blackwell games.

Of course, all games above have great story.

Which takes place in Syberia world, btw.

Which to me was frankly off-putting. You're supposed to be this detective type and there's practically no detecting to be done. No real "putting the clues together" of any kind. It's got this great world and atmosphere, but then squanders it in the gameplay department.

For all the praises Blade Runner seems to get, I thought it was a decidedly mediocre adventure game. =/

I liked it for what it was* - I never expected it to be some cyberpunk/scifi sherlock holmes game.

*I only started buying games when PC Gamer (UK) was first published (end '93). Before that, it was way too risky to spend that much money on a game, having just a pretty box as a point of reference.

About the Telltales games: they stopped interesting me after Back To The Future. Ok, it wasn't bad at all, but it was balancing between "puzzle-light" and "click to continue".

Late Shift.

It's a FMV game with no puzzles.

Hi, not really. Both are created by Benoit Sokal and have a similar plot, instead mamuts there are birds.

Sam & Max Hit the Road.

Thanks a lot for all your tips and descriptions, I'm sure they'll help others too, finding their next casual adventure to play!

There was this interesting remark about subjective difficulty.

Difficulty for me is linked to boredom and frustration : you are searching a long time for THE triggering pixel (that may or may not exist!) in dark corners of your screen, you have to go out of your game to search for solutions breaking your immersion, or write things down, or draw maps, or think logically and mathematically to conceive patterns or sequences (like a Rubic's cube), or remember the crucial world that was written on a half-buried piece of paper 5 hours and 25 screens ago, or insignificant details you are supposed to take notice of, or learn new things from the real world (Morse code in The Secret World), or run to and fro between screens to check *again* and *again* everything because you are not sure you are missing something, clueless where it is, clueless what it is, because NPCs you are helping aren't helping you with any tip or direction, and then you ask yourself: is it really worth it to waste hours or days trying to solve this silly video game puzzle, and feel proud, when instead, you could, you know, play a video game...

Easy for me is when you can combine everything in your inventory or click on obvious spots and you'll eventually find everytime the solution and can move on rather quickly because there are few combining possibilities, even if it sucks to progress solving puzzles by chance.

Actually logical puzzles are so annoying to me that I often don't understand them even when I can see them miraculously solved after 50 blind tries :-P

I found The journey Down Trilogy to be charming and relaxing. Most of the puzzles are explained in the dialogue with other characters, if you listen carefully. I didn't find myself stuck or lost on any occasion. Worth picking up on sale.