Answers to this question are always going to be based on someone's personal opinion so here's mine.
Clarity v Brevity
If you cannot know the set of options ahead of time then you have no real choice but to do as you have. However if the options are drawn from a known set then I would favour clarity over brevity and have explicit methods to set the options. These would also be a good place to add any rdoc etc.
Safety
From a safety perspective, having methods to handle the setting of an option would allow you to perform validation as required.
