There is no reason not to start a blog, even if you do decide to put the information elsewhere.
If your articles are well-written, informative, and cover ground that currently doesn't have many good resources, you will generate traffic and notoriety as a subject-matter expert. This is a great way to generate a small but loyal group of people who will be more than happy to provide input on/spread the word about any product on which you are working or will be working in the future.
There's one thing worst than no blog, that's a completely out of date blog. It makes it look like the company shut down x years ago. That said, the standard links are now Facebook and Twitter pages, which are even more useless than a blog. I'm assuming the blog is for a startup, if so, dump FB and Twit and try to add regular content. If it's not, I should have downvoted you...
I think you should.
What make a Blog good is not a lot of posts, and yes, good posts.
Yes, you should. Maybe this is an extreme example - but Paul graham writes articles once in a month / 3 weeks, but very insightful. So start a blog, if you genuinely have something to say / share and not for just filling it up with articles.
Shameless plug: use our service, Content Crooner. We will distribute your articles to hundreds, if not thousands of places on the web looking for content like yours.
Regarding a blog, if you are looking for consistent readership, you will need to provide consistent content. Perhaps rather than just waiting for the muse to arrive, you could make more of a commitment to creating good content. If you make space for good ideas to show up, you will find more of them come your way.