See, here is the real problem. According to what you just wrote, that +1 damage and accuracy feat is what you want. Other posters (and myself) think that would be a waste of our time as a feat.
Sure, you can say "give us more mastery feats!" but without knowing what those feats do, it is pointless.
Additionally, Prof + Fighting style + Feat.... is level 1. You want to demonstrate a high level martial character with a something they can accomplish at level 1. Sure, fine, the martial will need even more feats to get multiple of these fighting styles and mastery feats, but there is a factor you aren't considering... very few people will bother.
A low strength, high dex archer build is never going to bother with GWM and PAM. A low dex, high strength two-weapon build is never going to bother with archery feats, and is likely not to bother with one-handed weapon feats. Because the majority of the time... they won't be using those abilities. You could give fighter's every single fighting style, and since most of them are incompatible with each other, mostly this will not raise their power level AT ALL.
I didn't say the fest was good.
I just said what 5e considers mastery.
I wasn't talking about the specifics but quantity and quality.
How many fighting styles should the greatest knight in the kingdom have mastered?
How many skills should the greatest thief in the empire have mastered?
How mastering the sword and pistol how many skills do you expect the captain of the greatest pirate fleet in the East sea have also mastered?
And do any of they need to be supernatural?
Because in most movies, books, epics, TV shows, cartoons, anime, and myths, the Greats that are Mundane typically master at least 2 fighting styles and two skills at the minimum.
And that's before you get to the point of
grandmastery which usually does not exist in D&D at all.
This is because most games in the D&D sphere do not have a real sense of progression that can be felt in their lore nor mechanics due to the desire of the designers and parts of the community who prefer it to be loose, undefined, and simple
This thread is about stealing the progression of monsters to substitute for the lack of progression in Martial prowess.