I'm often faced with architectural questions wherein I have one or two general solutions in mind. Would it be off-topic for P.SE to post something like, What might the ER's for X look like to ensure extensibility [or maintainability, or simplicity, etc.]? along with one or two answers representing the options I've come up with so far?
And is there a better way to phrase that sort of question in a more concretely answerable way?
While self-answers are allowed, you should not base your design decisions on the popularity of the options you presented in your self-answers. The voting system is not meant for that and the reasons why people up or down vote are too variable to be an indication of which option is really the best. Perhaps the highest voted answer just used more of the popular buzz-words.
Additionally, as @Rachel noted in her comment, such a question has a very high risk to become too broad or to have insufficient information on what you have considered already.
In general, I would advise to present your options in the question itself and ask for an explanation why option A should be preferred over option B or vice versa. If there is an option C that has clear advantages over your current choices, then it will be presented in the answers, with reasoning why it should be preferred. And you will get presented with arguments why you should choose A or B, which you can weigh yourself. That you can't do just with votes.
