I’d suggest keeping it around one or two central, related topics. Reading about some ‘good’ blogging practices will generally show that they advise staying on topic. Think about magazines, you don’t open National Geographic and see laptop reviews or go to Gamespot.com and read about good house cleaning tips (but there probably should be). Choose a topic and write for that audience. Mixing unrelated topics may dilute your potential readership (unless you’re writing is extremely witty and engaging). And, as you stated above, if a primary goal for the blog is to land a new job, your personal views and beliefs probably don’t belong here.

However, if you’d really like to write about them, start a second blog with a different name and at a different domain, keeping the two separated. The possibility for a potential employer to see both blogs is still there, but lessens the chances if you’re only supplying them with one web address to visit.