Since you are looking at cameras with manual over-ride capabilities, Canon pretty well controls the lower price market with manual controls.
Their "A" series of cameras has been their best selling camera and it has little competition for the features it provides.
Any of the cameras you mentioned will do fine.
You do not need (or want) a high megapixel camera, because anything you put on the web needs to have a small file size to provide fast loading.
I use dial-up and if a website page does not load within a minute, I usually abandon it and go somewhere else.
I am looking for a digital camera for Web Site Design. I have a $300 dollar limit. I'm looking at Canon's PowerShot A95, A85, and A80. Any more suggestion.