With the exception of Haruhana who I thought was Rina at first, I could remember all the characters by looks.
Betty being single due to high standards makes sense, any other reason is bullshit. IMO she's easily the best looking female in this series, she's responsible and has a great personality. Being single for joke just doesn't work for her.
This whole series of events is setting up for drama and nothing else. Rina is not stupid enough to not use ....umm forgot the dragon's name the moment these bandits appeared. How the hell did these bandits get so close to them in a open field? When was this poison used that seemed to cripple them? No gas was shown and no one was shown getting hit by a dagger/dart/etc. How were these bandits not discovered either by the monsters or Ornell's group who later joined them?
Edit: One thing I forgot to mention, did the author completely forget that Rina is a rather skilled swordsman? She should not be a damsel in distress just because she out of mana. Why has her character de-evolved over 2 years!?