I think, Revealing Leon's potion ability so early was a poor strategic choice by the author. The story would have been much better if the ability remained a secret, leaving the characters (like the grandpa & elf) to investigate a mystery created by an anonymous figure. Like, investigating, who give the recipe that helped them discover the negative side effect of the potion.
And when it being revealed later, will make the character much more invested in Leon itself
Love your takes. For the maid, I think she trusts Leon enough and sees that he has potential. That’s why she changed her mind and chose to follow Leon instead. That’s what I think. For the second point, I think he doesn’t know how groundbreaking his potions are. So he really doesn’t care about the consequences and just chose to follow his instincts (just being a good free-willed man lol). It’s more like his close family is here to clean up his mess, although the maid genuinely did a sloppy job too on trying to keep him under the radar. But dayum, I still dunno why both him and the maid thought they were being discreet…it’s like it’s the maid’s first time being an undercover agent or something lol

2 thing that keep bothering me nwhen reading this,
1. The maid mention want freedom, but when Mc offer it, she then don't really want it?
2. The family want to keep Leon ability secret, but then it already revealed to many ppl, due to the hint(by the maid) and linked to potion given by Leon (truthfully, I don't think giving out potions to everyone is a smart move by Leon, instead he could just give to a few ppl in the mage tower, eg like the most important person or ppl he indebted to only (the grandpa). (since he also want to keep low profile too)