I'm going to call BS on this point here.Why does it have to be {da}?
We say "everybody", which semantically restricts it to people.
We say "every day", which semantically restricts it to days.
We say "everything", which means everything. Absolutely everything.
{ro prenu} or {ro djedi} or {ro da}... not semantically difficult and not a huge mouthful. {roda} is fine exactly as it is and means what it does. We do -not- need to generalise. If I have to stop and ask, "Wait, did you mean -everything- everything or 'everything we're talking about' everything?" then I don't want to speak Lojban anymore. Seriously. That is -THE- definitive point of why I speak and learn Lojban. One word, one meaning. {roda} means everything. Everything everything. All things. That is what it literally means. If we say that it has an implicit NOI clause that provides context, then absolutely -every- member of KOhA also has to have an implicit NOI clause. This is Not A Good Thing™.
I veto your laziness and suggest that you say what you mean.