I like to suggest a feature, which modifies the challenge checkers.
Let's take a look at this checker for example:
https://project-gc.com/Challenges/GC8X2G9/53125
You might have green and red fields. My suggestion is, that any red field or (or empty field in general) should have a link to a cache search. This cache search should show all caches with the correspondend or required value, like for example earthcaches with D/T of 4.5/5 when you click on the field for 4.5/5 or so..
Like the 360 from home, where you click on one beam and it shows the caches on it.
This would make the search for required caches much more easier and faster.
Hope you understand what i mean.