My advice is start with what you know best. Show confidence and do what you can well from the beginning. Once you get going then you can add more features to your program. I would say in general revshare is rarely used or I would say roughly maybe 90/10 pps/revshare.

Most common amounts are 50/50 or 60/40 revshare. I would concentrate on hosted free sites myself over hosted galleries as link list sites are typically going to provide you better traffic. If your site has custom/exclusive content give some of that to the affiliates to promote.

PPS will be based on what you need to survive as a company. How much your signups are, how good your retention is etc. As far as logging in for resources that is up to you, but the easier the better imho. Loggin in and getting links with your affiliate code is easier than substituting like XXXX with your affiliate code.

The rest you are probably going to have to learn on your own as your site grows. Each site, niche, etc., is different.