Now this is sounding a bit confusing. But, If I understood the first proposal correctly, you were talking about a quote option for every post(and maybe replies as well because they're technically post too).
And, your reasons for that is because, you would love to quote other writer's post in your own, right?.
So, what I'm saying is that, the quote option needs to come with certain attributes like original authors name, a link back to the original post, and also timestamps.
Unlike this plan quoting style below without any attributes...
Plan quoting style
The new quoting style would contain those attributes, Including a field for the actual quoted text.
I meant to say plain and not plan. Basically there's no overthinking it. Twitter for example has one, so just to mirror it.