Preposterous. You can't reward someone more for having an un-upgraded character. It completely devalues the whole idea of upgrading ones character.
How is that rewarding someone for not upgrading: I'm pointing out that when it comes to bonuses, someone with 5k base stamina, cannot kill as many with 10k. If you have more stamina, you can make more kills. If you use a kill:stamina ratio, then would negate that to an extent. I was aiming to make it fairer for those with less stamina, who will probably never get a bonus as it stands.
There was a mistype in my original post, which doesn't help, to be fair.
What about rewarding as a ratio of the amount of stamina? So someone who got 1000 kills, but has a max of 500 stamina (x2) gets a bonus, but someone with 1000 kills and 1000 stamina? With the bonus scaling somehow. ie rewarding when kill:stamina ratio > x, where x > 1.