Like pressing buttons in a specific sequence, or moving statues holding mirrors to a specific square on a grid to reflect a beam of light into a light sensor to open a gate...
I don't know if there's things already of this level of complexity in the game because I have yet to go very deep, but having done the same "find the button hidden in the blocks" thing so many times I'm starting to get bored of it.
I think that the current tools they have at their disposal are a bit limited.
Creating complex puzzles without also having equally complex environments is quite difficult.
Some of the puzzles in question have trapped players inside them before, hence why the current puzzles are as mundane as they are as well.
I would rather them have a strong base in these kinds of puzzles than a bunch of complex ones using the same tools that could potentially end a run.
But that's just me.
That said, I do have a few ideas for puzzles they could add to levels to make them less predictable.
Slime Mold: Basically, Slime Mold is an 'intelligent' mold, it knows how to distribute itself in the most efficient paths to get to food. Puzzles involving this and maybe, food dispensers, that you need to activate to create a bridge of some kind or get it through a maze so you can walk to the other side, would be cool.
Perhaps some kinds of Slime Mold could eat item drops, like Vials, Hearts and Capsules if you're not fast enough to grab them.
It could also be used in other ways, aesthetically like the Royal Jelly in that particular set of stages, as well as spawning pads for certain kinds of Lichen. I think a more interesting avenue would be having non-mandatory spots with a slime mold you could feed, that turned into possible vendors or helpers for that stage.
I did send an idea in a particular idea at the start of the preview for a monster, called a Mewkus, that was kind of like a Lichen and a Mewkat fused together. They came in bright colours and would run about eating your drops and things and you could either choose to feed them and maybe get a special item if they evolved or kill them and get your items back. If you got it to evolve it would become a catperson ooze that gives you a shiny trinket or a special costume item for your generosity.
It's not exactly a puzzle, but it could become one.
Entombment: This one is for Graveyards.
I figured, people seem to consider them 'rush through' levels because of how risky they are.
So why not hide the Elevator under a big, tomb-like structure, which you need to use switches/levers/buttons to reveal.
You could have multiple ones in a level and underneath the real tombs, there might be a phantom or other undead nasty waiting to wail on you for waking it up. Or maybe a friendly monster that thanks you for letting it out.
It could be interesting and change the pace of Graveyards once again. Hopefully for the better.
You should get the picture by now.
Puzzles are a hard thing to create, especially when they have to be the kinds of thing anybody can complete.
This means people with guns, swords or bombs need to be able to get past everything in the game.
It makes it hard to add interesting puzzles in this regard, since there are three possible ways people can do them.
They need to be quite neutral and this makes it hard to make them interesting or compelling.
But I'm confident they will add things to the game later on that will make the experience more interesting.
They have done so in the past.