Several hard-to-mess-up wordlists have been standardized. -- https://en.wikipedia.org/wiki/PGP_word_list

You'll want to be careful to consider homophones while also taking accents into account. E.g. if your dictionary contains "deary", it probably shouldn't also contain "dairy".

Or “dreary”, or “dear”, or “deer”. Unfortunate choice for the example!

Our approach is to only use 5-character words.

Great point!

This introduces a new type of risk - if it can be interpreted as a sentence, "moons" as a verb isn't really a clean word.