It sounds like the problem is that favor is awarded in a binary fashion. You're either the "best" at a given category, or you don't get any favor for doing it. I'm not sure how much of an impact it would have on the overall design to adjust this so that it's a graduated process, where points are awarded for each instance of an action instead - you get x favor points for each demigod kill rather than for killing the most, and so on - but it'd make it easier to understand the interplay between favor and actions in game, certainly. You'd probably actually want to use in game prompts every time you gain favor that way too, as that'd make it extremely obvious as to how favor gain works. It'd make sense to give an award bonus for getting the most as well, but you'd of course need to balance that to the higher levels of favor that'd be earned in a game.
You'd probably end up increasing the overall amount of favor given at the end of each match though (or decrease it, depending on how often each action occurs and how much you end up giving out), and you'd also more evenly distribute favor among players, so that might not be entirely desirable depending on what the design goals for the system are.
