These, to me, don't feel like moral dilemmas, but rather pretty obvious cases. I made a few suggestions to make them a little trickyer.

Ex. 1: Case A is self-improvement within risk-free (for others, at least) and readily available tools. That is just something you can do.
Case B is a violation of free will of another human. Changing their perception of reality so it better suits you is just another means of achieving control over their mind.

Suggestion: What if the altercations are not self-transfiguration, but a glamour, so it's not a permanent change? Does that change the moral implication, as you could now argue there is a sense of deception to the seduction, similar to B? Does it make a difference to pretend a reality that isn't there, even if it looks the same as an actually changed reality?

Ex. 2: A is equal to B. It's the same goal using the same means through different methods - there's no difference between legilimency and divination if both have the same accuracy and level of depth, as both target the other's thoughts.

Suggestion: What if you use divination to not predict her thoughts, but her reactions? E.g. you divinate (with 100% accuracy) how she will react to several different courses of action each. That way, you don't get direct access to her inner thoughts, but the opportunity to conclude them.
On the surface, this sounds less intrusive than directly reading her mind. However, people tend to not know themselves fully. As this would give you the opportunity to predict other people's reactions in extreme situations they themselves maybe never thought about, you could find out more about a person than they can know about themselves - and act accordingly.

 

Divining the best time/way to ask someone out sounds handy af.

Pity the magical orb doesn't show me any possible ways to get with people tho, it must be broken.

 

The Hogwarts Express is on a collision coarse with Draco Malfoy. The only way to save him is to redirect the Hogwarts express to another track, but that will kill 3 muggles.

Is it moral to redirect the express or to allow it to continue on its current coarse? Does the knowledge that redirecting the express irreversibly breaks the statute of secrecy and reveals magic to the muggles change your answer?

 

Muggles aren't people so there. You played yourself.

 

Well… we have cosmetic surgery, so… a spell can’t be that much different. At most, it’s dishonest.

changing someone else has to be wrong, right? Unless they consent to it…

 

With Rowling's indulgent attitude towards love potions, I'd say date rape drugs are canonically considered a fair game. This covers the case 1.b. Expanding the mindset of magically conquering the chosen partner, all of the points seem to be more or less inside the Wizarding morals, with 1.a being the least befitting a proud sorcerer's image.

The situation looks foul on the first sight, but kind of makes sense if you include magocracy, where the skill at magic is the main area of competition. So if the victim get affected, it's their own fault of not being wiser and witter.

This brings out the possibility of different metric of Wizarding morals: instead of operating in consent and untouchability of another person, it could be comparing the weight categories of involved parties, usage of unhonourably powerful objects and spells; the sporting qualities in the game of love.

Law is a different matter, of course.

 

The more I learn about the Wizarding World and think about it, the less I want to go there...

 

A bit of a follow-up.

Magical society cherishes guile as one of the key virtues of a sorcerer, no less so than the arcane knowledge itself. This, I think, should be the main principle of morality in dosing your senpai with a love potion. It's ethical because a victory by deceit is honourable.

Zabini, son of a black widow, is invited to Slughorn's parties as a wizard of promise. His mother, in all her suspected horrible deeds, not only hasn't yet been caught, but keeps attracting new victims: a witch of an enviable ability. Everybody and their elf knows Malfoy was a Death Eater. So what? He slipped away like a wizard should. Veelas affect most of men with their auras. Should we perhaps ban them from exploiting it on the WORLD CUP's freaking JUDGE? Nah, the bloke's should've learned some Occlumency, the fool. Maybe the next time we'll make it the job's requirement so we are not caught this easy.

This is Wizarding culture for you, my good muggles.

 

Based and Magic is Might pilled.