Well my own goal is 1000 a day. That would be as an affiliate and with programs I work on. To me that would be excellent, and I have no doubt it is possible, like you said there are many affiliate programs out there. You just have to keep tweaking your own sites to produce more results. And look at everyway there is to promote, organic, paid, and email.
I do remember the 3-5 sales a day my first few months and that is good as well, it pays the bills
Posting a gallery a day to TGP's should get you that easily. Especially if your optimizing your galleries for SE's. You might only make 1-2 sales a day off that gallery at first, but when it hits SE's you will do more.
I know, that there are many affiliates that join programs, never really promote them and bitch that the program sucks. I don't think many suck, you just have to find the best way to promote them to make the sales.
Also, I have seen many affiliate programs that could make changes to their own landing pages and they would convert better.
So it really comes down to learning traffic. How to get it, how to convert it, from your own site getting it to where it goes.