Like here: Study French, English online! (with big banner)
I think the template doesn't really matter that much. It is more like the ad placement what matters. And of cource it depends on the visitors too. They are the ones clicking the ads after all.
If you are trying to get subscribers to your email list. The best place to put the form, is in the top right, above the fold.
But again. If your website looks like piece of shit, and is full of blinking awful looking pictures. No one is going to stay in your website more than few seconds.
So. If I had to choose good, or ugly looking. I would definately go for good lookin.
A couple of things not yet mentioned in this thread
- if your site looks MFA it is much harder to attract natural links, so for high earnings now you might be paying a price in future traffic and earnings
- for certain affiliate products a site needs to look good. If I'm trying to sell vacations it needs to be a site that people look at and think they can trust, which won't be the case if its covered with banners and adsense
I don't think I really have a vote because I cannot make any money from AdSense to save my life. My guess is that the ugliness of the theme has nothing to do with it. Rather, it's more your placement on the theme (which has been mentioned, but I wanted everyone to know I suck at AdSense placement).
I don't think it matters if its ugly...as long as its not too ugly to scare people away and/or turn them off. What is important is that its easy to use and not confusing. If its not easy to use, people will get frustrated and seek their information elsewhere. There should be an easy, obvious way to contact you and find your phone number.