My main complaint about a lot of vegan foods is that they seem to take so long to prepare.
I think any type of food that is healthy and considered to be a 'meal' will take a while to prepare. I don't think that vegan food is really that much different in preparation time, it just depends what you want to achieve. I eat rice or pasta or fresh fruit / vegetables or cereal etc. Nothing takes me more than a few minutes to prepare. But similarly, if someone is a meat-eater, and they want to make a 'proper meal', I think it'd take them just as long as a vegan proper meal.