The design is dumb and the guard is bad. Those aren't separate criticisms. If the guard were more in proportion, it'd just look like a standard fantasy sword from someone who doesn't know swords very well. The absurdly oversized guard is what pushes it from generic to genuinely awful.
On that it's because it's a taming skill not a mind control skill. Taming skills work by maximizing positive associations to the point they want to fulfill the orders usually.
On honorifics keep them they feel more natural than Mr, Miss etc. since they aren't really used as much anymore and most people reading this are already used to the Japanese honorifics.
Will he have to deal with the loss of image this causes especially to his father? The way he brushed the issues with the servants was kinda alright but when it's in public or the servants mistake threatened his live that is a bit harder to ignore... Or will the author keep expecting 21st century...
To be fair he wouldn't care about the extortion and raping but he would certainly care about the "under my patronage" bit. Since not respecting that would undermine his authority.