#1. -1, for the fact that it would need to implement new ideas everytime the event came to pass. If it did keep the same prizes than the players would be bored or not take part as they'd have already accumulated all the stuff then it's just down to being greedy and wanting to look rich, or just to stop other players from obtaining if you have more skill than they do.
#2. I like the idea of this however -1, the rewards would need a better thought as it's easy to spam an alt account to boost your wins as i know for sure some of the top ranking on bvb aren't even that good. This might be the reason why there are no rewards for top rankings, but i don't know.
#3. Maybe a later addition to the pvp if the previous options where to be accepted and worked bringing in a stronger crowd to pvp. But to make the time to implement this option may be time consuming, and even if it did i generally don't think enough players would partake in this meaning 7/10 you would have the same opponent. Plus if a player is better than someone else you shouldn't change the settings just because someone has better skill than the other person they need to keep playing and just learn to get better rather than wait for updates to make it so they get spoon fed wins without really doing anything.
#4. There was a calender event which allowed players to defeat each other and staff to earn certain pvp only rewards which was Bv2 III e.f which is not trade-able or anything. However, i can't think of any more items won by this. Since bot stract hasn't got much of a beneficial use try changing that perhaps to buy special pvp items, but first a big discussion with the players as you know how some people cry if something is to op and refuse to play. -1
Overall, -1. But good try on the input;).