Of course no ones perfect, that's not what this show is about, and a good thing it isn't. I choose the Black Knights based on my observations and by the results they achieve compared to the stagnate and decadent Britannia. I'm like Diethard I guess, I know when the ship is sinking and when a time for change is needed
. And going by the Order of the Black Knights mantra I can find a harmonious setting were they to win while at the same time I compare how I would face constant danger under Britannia's system of rule. In this sense I'm also like Lelouch, I go with something that seems like it would achieve the best overall results.