In the manga, seeing the trap and reverse trap fawning over each other is easily the best moment.
He is "Attributeless", so he has extremely fast magic regeneration speed (practically instant) due to the air being full of mana (principals' thoughts).
He's the illegitimate son of a noble.
He learns to read & write by 2 years.
He makes up a story to hide his knowledge at three.
He understands the worlds' medicine enough to fetch & compound the ingredient required to remove a "magical" disease, just from reading two books for a few minutes. Kills three goblins (knife, break, magic grenade launcher + sword) and retrieves it.
His old shishou was a f**king tea otaku, I don't know how I feel about that.
Introduces non-magical ways of creating fire...
Redefines magic by himself using modern knowledge to create a pseudo-handgun, rocket launcher, sniper rifle and kevlar ropes. And 1mm kevlar rope being able to hold 60kg (~130lb) is true from what I can tell.
Then we skip to when he's five. He outdoes his teacher easily, using the generic full-physical boost magic that he modifies heavily, along with an original scaffold based magic that makes "steps" in the air, letting him easily reach the speed of a car. By "harmonising" (syncing... frequency?) with the airs' magic he can fully recover his massive pool in three seconds. Oh, and then there's the generic "search" spell letting him "ping" sonar magic in the air. Oh yeah, it's f**king hard to follow a person that can suddenly fly above a forest and cover an ocean in minutes.
Saves a generic fantasy beauty Elf being attacked by generic bandits, who treat her as an object. Leaves the bandits to die by bear-sans. Fixes her up, shows her his "Wyvern OHK" magic, teaches her to fly (wind please!), finds out that she's a 252 year old, arranges to meet her after 10 years (by "coincidence", after graduation), returns her and heads home. A week later, meets battle junkie on the way home, beats him up a little, arranges to meet and play with him near daily.
Also, the idea of taking 20--21st century Anime Mecca suits, making them, adding ejection seats lends it more to the idea that "Everyone except MC is noticeably dumb" than anything. Throwing invisibility into the mix, having the Black Plague be solved by children and so on and so fourth basically says that turning the world against them is not good. Saving a ship is better than not.
Also, the MC can't speak or understand English at all, so he would have failed his exam if not for the UN practically saying to the Principal "Keep him the f**k in school".