Good points san, really like the idea that if you're next to a teammate who's getting points, you also get some sort of indirect points for it (so you can guard archers as a shielder/piker and get points when they do).
Also I've heard other people say what you are, that you need to get over double the average of both teams score for the round to get valor, I thought it was only your team. if it's both teams, then yeah that should change right away so it's only getting double or more the average score of your team, not the enemies also.
And it shouldn't be points given for how much damage you do the enemy, everyone should have a fixed amount of points (or fixed amount of points per level of their char) and if you take away 1/2 their HP, you get half the points allotted to the player. I also noticed if I go for horses (not the riders) I can rack up more points than killing the rider (if you get horse + rider, even better). I think horses have too many points allocated for them.