Page 6: Why is the text in that bubble just romaji, with a perfectly good translation instead given separately in a note?
Page 15: The sign is not the same as the previous one. For one thing, this sign has "水着" (swimsuit) on it. I get not wanting to translate that partially obscured sign, but at the very least, the translator's note should say something like: The sign below is similar to the previous one, but replacing "food" with "swimsuits"."
I like to create translations that I would enjoy reading, which is why the text on page 6 is in romaji. In my opinion, there is no exact equivalent term, only something that comes close to the original meaning. I also find it more pleasant, just like using "Onee-chan" in some previous chapters. This is simply to prevent the translation from becoming too rigid and repetitive. If everything were always the same, it would be quite dull

Regarding the issue with the sign, yes, you're right. But I was genuinely afraid of ruining the original artwork since the background and the balloon were glued together. I didn't think it was worth resorting to a makeshift solution just to translate that part.
And a curious fact, since you mentioned it: Every time you read "Bikini" in the story, that was an adaptation, interestingly they only mention swimsuit all over the chapter.