My two cents about what I don’t like happening in the current challenges:
hosts playing a guessing game with the entrants about what they exactly want (or not exactly knowing themselves) - I enter to build cars, not read minds
walls of flavour text - if I wanted to read a book, I’d just do that
0 techpool rules - I treat techpool being there as the default, and the more I have to design the car specifically for the ruleset, not generally for the car type described as I see fit, the less likely I’m to enter - I like to keep and reuse cars
nitpicking completely replacing a general view - when I spend even an hour on a car I expect the host to spend even just 5 minutes to write some general “this good, that bad, something average” instead of just “sadly X is below expected so it won’t be considered” packed in a few more words
I’ve gotta admit, I actually like the more vague requirements. It adds an extra layer of challenge to the challenges that forces you to really read between the lines and work out what you think works best, which could either be a total gamble or a good play (see my car in QFC23, took a gamble and lost, but hey I went for a specific angle and by all accounts succeeded with it, it was just the wrong decision in the end).
Hell, that’s why I really adored Cool Wall (CW5 when), everyone came to their own conclusions about what the hosts wanted and there was a large variety of cars entered for it.
Lemme put it that way - I like it when the vagueness of the requirements fits the broadness of car types that could potentially succeed. The cool wall system is nice, as it gives solid reference points without being too explicit. Rules broadly fitting, say, any mid priced sports car, while the host secretly wants an AWD sporty GT with an N/A engine and will judge accordingly, are not so nice.
I think the vagueness that promotes fresh ideas doesn’t have to be the vagueness that risks binning for being a bad psychic.
As for walls of flavor text, personally I like that, but would agree that there should be mandatory summaries for those less into the lore and roleplay.