I didn't find it easy! As you say many of the clues are very oblique and the answers obscure. I agree it is a weakness that you can finish the puzzle without understanding all the answers.
Thanks Malone. I'll keep trying then.
I can see van fits well into the clue you used as an example, but limo for instance doesn't fit in to 26 while allowing the clue to still make sense - does it?
Lumen, I didn't bother with the detail of the vehicles - as long as you've got a few, you know that, collectively, they could be described as '??????' How would the title affect '???????' (bearing in mind the use of 'appropriately highlighted' and earlier references to colouring).
The preamble mentions that 'one third of the grid' is to be highlighted. That's a huge chunk … maybe worth a hard stare at the grid (if you've filled in a fair bit!).
31 You'll know, I hope, from the preamble that this is an abbreviation? The definition is 'people meeting in Strasbourg'. There's a letter to be removed in the second word.