Ok, thank you! A word of caution though: My reason for not fixing all those errors as soon as I encounter them is that I want to understand how they came to be in the first place, and what other errors they may have resulted in, in order to fix those as well. I guess the Office case isn't much to worry about; the description is apparently taken from the Office disambiguation page, which itemizes other interpretations of the word, but doesn't suggest that "position" might be yet another item (and there is no English Wikipedia article linked to the position (Q4164871) item anyway). I was looking for some kind of "public office" though, but I threw the whole issue aside when I found that many of the national public offices have their own unique items, sometimes subclasses of position, and I don't recommend merging them without a very thorough understanding of all the aspects described in the different linked articles.
Case in point: I'm now considering undoing an earlier merge of the Swedish Resecentrum (public transit centre) article item with transport hub (Q2298537) (and probably also of the Finnish equivalent) as I don't think the merging editor realized that a transport hub may include also cargo handling. There are oil and container shipping terminals among its subclasses! But the ancestral class tree doesn't seem to be very carefully laid out either (I have spent almost a full week investigating the 238 subclasses of transportation stop (Q548662) since I learned about the new public transit stop property and wanted to know what it referred to before suggesting some appropriate qualifiers to it)...
But I very much enjoy this. Wikidata is quite close to what I imagined an Internet web of information might look like, before the World-Wide Web appeared.