I don't know if it's alright to ask about manga on an anime centred forum but it should be fine, right? I feel like every manga I've read either has really slow progression, loses quality drastically by creating pointless drama or has a trash ending.
I'm looking for manga either Fantasy or Romance genre. More specifically if you go down the fantasy root I want a protagonist that isn't a coward or a beta male who nuts at the touch of a woman and who becomes ridiculously powerful eventually. As for romance I'd prefer if they don't beat around the bush too much and actually get together fairly soon into the manga rather than it being a game of "flirt until the penultimate chapter". I've not read many manga so don't worry about recommending one i've already read.
I recommend To Your Eternity, although I suppose it may hit a few of your red lines depending on how you look at it.
But it's pretty much the best fantasy manga I've come across thus far and I've waded through a lot of shit. It's from the same writer of A Silent Voice.
The story chronicles a young child named Kaidus--Kaidus Reilt Paltos--who possesses magic power since he was born.
He isn't a son of a lord, a duke, a knight or a king who normally awakens himself to magic when reaching his age of teens.
His father was a former mercenary and now is serving as a village guard, and his mother is doing various laundry jobs for the villagers. Both are working hard everyday to earn little money.
His control of magic is a gift as his family thought, but unknown to them is that he is actually an ancient wizard who was reincarnated into the current era.
Back in the very distant past, he was a man known as Rhultal--Rhultal Vox Treval AnDargus--who had struggled to achieve strength, rose from buttom to top, became an avenger and faught for what he believed.
Now, retaining his past-life knowledge and holds onto power incomprehensible to the present time, he must search within the myths and legends for clues connecting to his origins, to what happened to his former adversaries, and to this world.
And despite of being reborn, his policy never fades.
Spoiler for Main Protagonist's Characteristics:
As a toddler, he obliterated the bandits who attacked the caravan he along with his parents traveled with. Before they attempted to beat and rape his mother who tightly embraced him, he bursted out his magic and popped their blood and organs inside out.
The seven y/o boy, like a silent assassin in an open area, slayed a monster rampaging around the city plaza and saved, not only the people in the vicinity, but an old knight commander who put himself in danger following his duty.
Rejected the proposal from a local lord regarding his daughter should be married with him, for he didn't want to be "a shackle that chained her." He insisted to let her have liberty to select what she desired and the future what she deserved.
The youngest person and the only commoner ever enrolled in a prestigious Zorin Academy for mages. Due to his appearance and status, most of the students sneered at him, but the quiet youth didn't care less of insignificant creatures who were irrelevant to his quest.
A woman belonged to high nobility and was the top of her class looked down upon the new transfer student. Filled with arrogance concerned to magic as she thought herself was the numero uno, she wanted to teach the boy a lesson. However, what happened later was not what she expected. In a mock battle, the unassuming boy's sheer power instantly crushed her and left the area like it was nothing.
Curious about the youth's terrifying strength, the academy's headmaster decided to put him into a "test" of magic. Being the most high-ranking mage himself across the continent and only few on par with his level in the world, the headmaster and three of academy teachers ambushed the child with all his might, only to lost his left arm as the fearless boy retaliated. Then he was convinced that the small monster belonged to the lost rank which in this world only ever described in legends and myths.
In an alley within one of the city's district, a group of malicious sons of nobles were torturing a lone helpless little girl. A passerby child happened to stop by and noticed the scene which flared up his rage. He confronted and faught against the boys by letting them felt what they did to the girl, healed the girl's wounds with his magic and brought her home safe.
Responsible for the incident, the child was convicted, subjected to a trial and eventually won, but the noble lord, the father of one of the malicious boys, was not convinced and kept on lashing out against the stoic child for he wanted to see a solid proof. Irritated by the man's despotic personality, the child obliged and ripped off the stubburn man's entire arm in front of many people.
An organization operating in the darkness wanted to recruit the indifferent young boy as they witnessed and became interested in his abilities. Upon his refusal, its members resorted to violent resistance, but they were treated like bugs as the cold-hearted monstrosity fought back and flushed information out from them with force. He learned that their organization was responsible for chaos which had perversed the world many years. Using his extracted info' at hand, he nfiltrated their base operation in the continent and massacred every member including their leader, and left only few who were later captured by the guild.
A young woman described him as a coward upon seeing him didn't fought back against the sword training students who ganged up to him, despite her old knight grandfather's praises on him. She hadn't acknowledged that the boy didn't want to get involved with unnecessary conflict. Another young woman, on the other hand, became interested in him upon learning the boy's demeanor as he calmly rejected her lord father's proposal. Bookstore owners thought of him not a typical child as the boy obtained many various books from them. However, unknown to all, including his family, was what he actually possessed: unparalleled magic power, strength and ancient knowledge which cannot be attained in the current era, thereby placing him as being the most dangerous person in the world.
Spoiler for Some Parts Of My Review Re: Main Protagonist:
A main protagonist who is a rotten spoiled brat NEET that lashes out against his parents and runs around like a fool alone in his room. Then upon his pointless death, he is reincarnated to and suddenly turns overpowered in the new "Isekai" world.
A main protagonist who is an emotional dimwit and freaks out with anytihng when it comes to girls.
A main protagonist who lusts as a drooling chimpanzee for anything related to fame, luxury, status and wealth.
A main protagonist who transforms into an insensitive snowflake when dire situations arises and squeals like a pig when confronted by enemies.
A main protagonist who gives up on his goal and acts of being a sore loser after being rejected by his crush whom he lusts for.
A main protagonist who turns out to be a whimsical little puppy before and after he kills one, two or a few people.
A main protagonist who is actually a pervert that chases every inch of body parts of women and tends to daydream of getting a harem.
A main protagonist who is always getting plot-armored by insufferable edgy willpower in order to look "cool and badass." Afterwards, all the women around him transforms into mindless pussycats who likes to throw themselves and loves to fight over him.
WELL, NOT! NO WAY! NEVER!
Kaidus is an adult in a child's body. Unyealding, he unintentionally makes people around him bewildered. Sheer amount of magic power and lots of ancient knowledge on his arsenal ever since he was born, he doesn't use them to obtain a high status of life to get arrogant, he doesn't use them to show it off around people to look good, he doesn't use them to force innocent ones to blindly follow him. Instead, he intends to hide it and uses it only when necessary and when situations required it.
Bookstore owners considers him as a regular customer who devours their shelves as the little boy often obtain his choices of books, for he loves to read books regarding the history of this world. Actually, he is searching for information that will possibly connect to his past.
Stoic demeanor and quiet most of the time, he sticks to his purpose and doesn't waste time on trivial matters and unnecessary conflicts. However, in spite of his nonchalant attitude, he cannot stand idily when injustice occurs in his line of sight. Despotic people and pompous elites are what he despises the most, he doesn't want to be lumped together with their ilk. That is why wealth, status, luxury, fame, and even women doesn't interest him one bit.
Under his new body, his strength is not on par with the level of what he was before, but he trains everyday to hone it. In fact, his degree of mana is now very far beyond compared to a high ranking mage in the current period. With such a power at his fingertips, he sworn to protect his family and will eliminate the ones who dares to be a threat to their lives.
__________________
"I am the echoes of those who had been slain by the metal of injustice. I am the shadows of men long silenced and hidden from the light. I am he who rides the black winds of carnage. I am death himself. Prepare yourself, for when next we speak, it will be face to face. And you will know that your death has come."
Cold eyes, carrying frozen death. Hair of deep silver, more radiant than moon glow. Body of pure evil, a darkness that dims even the golden sun. Awful and terrifying, is its presence on the fields of blood upon which it visits. Like a wraith shrouded in death and decay, it stands alone and absolute.