There's not going to be a "right" answer to this question.
Look, if I want to get back into publishing acoustic guitar reviews here, then I could put out two or three a day, that they'd be GOOD too. You see, that subject isn't any work for me - I know it, and can just "bust it out" at will.
Everyone should they think about it - will realize that they too have a valid niche like that they can just produce in and do well enough with.
...but I personally like to learn things, and when one is learning new information it's difficult to create something concerning what one has only just learned instantly.
So it's all a matter of priorities, really.