GetOldest and cache attributes

I'd like to do a challenge where you need to find the oldest caches containing certain attributes. For example, my first foray was going to be the 10/50 oldest tree climbs in Ontario, Canada. Unfortunately, it doesn't look like this is possible currently, because GetOldest doesn't return the attribute sets of a cache. (I would assume this is the case for GetHighest/Lowest/Favorites as well, although I haven't confirmed). I assume this data exists in the database.

Would it be possible to add to the params for those methods, to request certain fields of the results (as with GetHides)? Or alternatively, if there was a (fast) query to return details about a cache, given a GCcode (and that isn't necessarily a user's find), I could also work with that. Thanks!