I really wouldn't re-open them (unless you made changes to the first one).
Regarding the first one, you ask (in the body),
Suppose a layperson's lawyer operates using billable hours. Besides the following, what else can a layperson do [to minimize billable hours]?
This is too broad, just as the title suggests. You eliminate some other options, but there's nothing else holding all sorts of answers back. That is not good. It was closed as "off topic"; "too broad" would be another good reason.
The second one is purely opinion-based. As the body says,
For example, how many different lawyers should a layperson seek advice from, before retaining anyone?
I'm a math-y guy, but there's no way I can come up with an formula or data to conclusively give a good answer for this.
Can they be improved?
I suppose you could overhaul that and ask what lawyers do that increases or decreases their billable hours - in other words, looking at it from their perspective, not that of the client. I don't know if this is on topic, but if you ask for specific examples, perhaps it might escape being too broad. You would have to ask if certain things are common practice, though, and not just practiced by one out of the thousands of legal professionals in the world.
I don't think you can save the second one. It's all opinions.