Working hard to find the right category is appreciated--many website owners don't bother. Which delays not only their site review but everyone else's.
And the focus on the website rather than the site suggestion is also realistic--websites without good suggestions can get listed; suggestions without a listable website don't.
However, I'm not sure exactly what you mean by 'respectable' or 'worthy'. But that doesn't so much matter. What's important is the ODP guideline. The directory lists sites with "significant unique content". A site suggestion will be more likely to be used quickly if (1) it mentions something unique about the information on the site, and (2) that unique information is especially interesting to surfers.
How do you know what's interesting to surfers? In particular, the sort of surfers who volunteer to review websites for the Open Directory? In detail, you can't. In general, they reflect the same combination of curiosity, acquisitiveness, and effort any other random collection of people would have.