Dude can probably teach Lusha swordsmanship a little bit longer, but Luna might need a proper magic teacher. Is it the apprentice magician, who won't be an apprentice anymore after so many years?
Allen's conversational skills are shockingly bad, both last chapter in not explaining to his former party why he'd just leave and here in not telling the villagers in 8 years(!) that he found the two girls abandoned and just decided to care for them.