It's become apparent to me at this point that there is a very, VERY large gap between the 60% credit and 100% credit threshold, as I was able to get 60% solo on a ShB S rank as a tank by spamming ranged attacks for maximum enmity with only 30 seconds of combat whereas doing the same thing for four minutes still only got me 60%.

It also bugs me that there's only 10%, 60%, and 100% as the reward tiers. I think there ought to be at least one tier between each of those as well.