Just a general note: top-down never really works for me. Unless of course I'm on top.
In all seriousness, if you want those of us on the front lines to pay attention to a naming convention, you have to get our buy-in on it. We are all volunteers and we are doing this for whatever reasons, with different target audiences, etc. Either you need our input before we accept a "naming convention" or the system has to be adjusted so that it is "dummy proof," that "junk that doesn't go anyplace else" has it's own field, etc. Otherwise, expect it all to be ad hoc and constantly changing.
I have a personal convention that I follow, and it contrasts sharply with a few of the other conventions presented on her (I refuse to use the suffix for titles, for instance, wherever I have a say, and I will purge all-cap last names as I come across them - all caps last name is a style that emerged in the 19th century that probably should be left behind in that century - and probably should never have been started). But I'm only going to be as strict in implementing my preferred style in my areas of the tree, and in the more common areas, I'm only going to be concerned with accuracy (I will defer to sources for the most part, but references to the Holy Roman Empire before 962 I have declared a Holy Crusade against). Of course if I run into: "George van de De Serbia Swabia of Prince Germany", I'm going to correct that in my own style, no matter the other "naming conventions" floating around.
And that's my "dos pesos chilenos"...