If it weren't for the last track of Classic this would have been an easy, relaxing 4... but that last track... ohhh that last track!
There are maybe a half-a-dozen really tricky ones - but most are a few minutes enjoyable work. The fact that you can "carry" particles around with the singularity/gravity well control (required for "It's a Mess" trophy) makes some of the puzzels significantly easier (I wouldn't have been able to beat the game without this).
Also of note is the fact that many of the trophies require specific tools/items to be used but there are no instructions in the game. Two of these specifically are NOT obtainable in the "Modern" track list at all.
"Event Horizon" requires the use of a "Black Hole" - this is an actual scenary object only available a very few later levels in the Classic playlist NOT the tool that looks and acts exactly like a black hole.
"Bouncy, Bouncy" requires the use of a "Deflect" control which is only found in the Classic Playlist. It's NOT the "reversal" control found in the Modern playlist.
All that said most of the trophies are on the easy side and the game is, with some glaring exceptions, frustration-free.