I must admit I am to lazy to read all the terms and conditions wherever I surf online on a daily basis.
Anyways, since I got my lousy first hub on the first page in Google I would say my practices work. Rating in hubpages however, tends to have something to do with: number of hubs, score of those hubs, your activity in: comments, forum, and answering as well as posting question and anything that has to do in a way or another with your activity.
On the other way I didnt heard yet of a photo rating, but I am sure that if it exists, it have to have something to do with your hubs where the photo belongs.
Finally, nobody will uncover the "whole secret" for you because that can be used for abusing the system. As for the "how high" I guess sky is the limit :D
Hub owners really need someone to rank in 1st position first in order to compare others with that position. Think about it.