How does your niche site look?

I keep seeing all these posts about how these guys create 10 or 20 niche sites and try to make a couple dollars a day with them. Ok, so your writing articles, putting your Adsense or whatever form to monetize. But what does your design look like?

Are you guys just taking a random Wordpress template and using that? Are you actually designing graphics/banners for your niche site? Do you wait to see if the site gets bigger, then if its successful customize it?

It seems a complete custom site would lead to more conversions. Maybe its just not worth the time/money until the site does well.