Hi. Is it better to just use adsense by itself or mixed the website with other ad programs such as bidvertiser and adbrite?
Hope this clears your doubt. https://www.google.com/adsense/support/bin/answer.py?hl=en&answer=48182 "Competitive Ads and Services In order to prevent user confusion, publishers may not display Google ads or search boxes on websites that also contain other ads or services formatted to use the same layout and colours as the Google ads or search boxes on that site. Although you may sell ads directly on your site, it is your responsibility to ensure that these ads cannot be confused with Google ads."
no company pays better than google. Because of that, you should have only google ads. Never forget my advice.
It totally depends on your niche,choose a niche with high paying keywords..wallpaper niches are performing very poorly with adsense...