You're at a serious risk of running into a "Mary Sue" issue if your protagonist lacks flaws. It's dubious that you can create a truly interesting story with the protagonist being absolutely perfect, unless you think it as some kind of satire, where that perfection is actually a flaw.
For example, take "The Iron Dream" by Norman Spinrad, a "a metafictional 1972 alternate history novel". It's a book-within-book thing, with like 90% of the content being verbatim contents of the inner book: "Lord of the Swastika", by Adolf Hitler, a renowned Sci-Fi writer, winner of the Hugo award.
The protagonist of "Lord of the Swastika" is perfect in all respects. Feric Jaggar is a proud, young, strong and genetically pure male with blonde hair and blue eyes. He reinforces the lacking strength of the falling bastion of genetically pure humanity and begins conquest against countless mutant hordes, unstoppable and unchallenged.
Only thanks to "Preface" and "Afterword" what would be really just a total purple prose takes on some perspective, placing the book within a world where IIWW never took place, where deep flaws of character of the writer (Hitler) are reflected as special strengths and preferences of the protagonist, and the whole thing becomes a strong satire and a social commentary instead of just author's wet dream.
Note, your example:
the protagonist is thrown out of a seemingly normal, happy and functional life only by the intervention of the antagonist.
This is the flaw. Lulled into comfortable, calm life; weak; incompetent as a fighter, and lacking courage. A hen-pecked puppy becomes a war dog. Or opposite, the flaws become the strengths. Or even more opposite, a character appearing flawless in the beginning begins to exhibit increasingly more flaws as the story progresses.
Without flaws there is no difficulty in resolving the conflict. Without difficulty there is no sense of reward, no sense of risk or danger. Perfect protagonists are boring.