To be honest I hate saying this because it sounds horrible in my mind, but the general ethos I went with is to emphasize working efficiently rather than excessively--but at a constant rate throughout the semester.
So I did not do thorough readings at all, but I did try to pay a lot of attention to which aspects of a case the prof focused on--and then spent ~5-10 minutes after each class thinking about the class experience/notes/thoughts and incorporating it into my notes.
I basically did not bother outlining (except kind-of for contracts--but that was mostly just because Galbraith is closed book/rules oriented so I wanted to have to go over it all thoroughly (I did get my best mark in Contracts though, so maybe I should have outlined everything)), but spent that time instead going over my notes/other outlines and really trying to figure out which parts I did not fully grasp. I did make spreadsheets with every case in them for my two open book classes, I think this worked great--you just go down the list of cases (each essentially representing an issue) and try to apply them to the facts you have.
Right before exams I only did one (in total, not per class) full exam (and even then it was more like very detailed outline) which I do not think I gained a lot from, instead I focused on knowing the law before I took the practice exams so I could just outline answers with some confidence that I already knew the law and practice was mostly just for spotting issues. I did go through briefly every one of Baker's (there are like 10) practice exams, but none of them with a lot of determination. I actually do agree with your general feeling that the sample answers are more useful than the prompts--hopefully reading them for other profs is enough.
Very importantly, this ethos of working efficiently (but a little throughout semester) helped make me very unstressed and relaxed during finals, which I think is a big bonus. I hope some of this helped, I am not sure how well I said it, or even how I managed to get the grades I did to be honest (still expecting a big drop next semester).