I submit that 孝 is a very Chinese concept. (It is possible that other ethnic groups in other parts of the less developed World may have similar concept, but not in present day Western societies, hence the difficulties here)
Translating it to mean mere "respect", "devotion to family", "love", does not capture it completely.
I would say that you are correct. The term "filial piety" is not widely known or commonly discussed in the US except when learning about Chinese culture specifically (perhaps Japanese and Korean culture as well, as they were strongly influenced by Chinese culture in the pre-modern era). The notion of "devotion to family" is much more ...
There is no suitable direct translation. Usually "obedience (to parents/elders)" is chosen. But that is way too far. From the idiom 百善孝为先 (孝 is the top of all good deeds) you may understand a bit. You not only have to obey/comply, you need to be very kind and consideration towards your parents and grand parents. Most important of all is that ...
It depends on whether you use the time term as independent qualifier (can't add 在) or as part of a phrase, especially the prepositional phrase (在 usually must be added), and my suggestion is to avoid this type.
我是在1997年喜欢上汉语 vs 我(是)1997年喜欢上汉语(的), 是 and 的 purely for emphasizing;
我在八月到的上海 vs 我八月到(的)上海, again, 的 for emphasizing.
Also, I recommended try to avoid ...
We call it 单押 in Chinese，which means that sentences have the same or similar vowels between sentences. The end of each sentence has the same vowel. It's a type of rhyme scheme，not a type of music though. You can find it in many types of music.
Here's some other examples:
东风破 (by Jay Chou),
一路向北 (by Jay Chou),
禅舞不二 (by Wilber Pan).
Yes, you can put 在 in your examples. And...
Pay attention to words like today/tomorrow, you can only add 在 when the time goes as a noun rather an adverb.
明天会更美好: do not put 在 before.
In particular, for the first example, 在 must be added, check the differences below.
早在八月...: since August.
（在）八月初...: in early August.