I know I did a similar post last year. However, this time, I'm only talking about the Manhwa version of the character, not the mainstream light-novel version so this isn't just a copy of a prior post. Also, FYI, this isn't a proposal or discussion.
Now, for Magnificence, Fang Yuan easily hits the bill. He maintains composure throughout nearly the entire run of the story and rarely ever loses it. He's very smart as well as he consistently comes up with brilliant plots to ensure he gains more power and is incredibly persistent as well. For example, in order to obtain a Liquor Worm (which is treated as an incredible power-up in-universe), he drank many bottles of wine at the young age of 15 to give out an aroma so that the worm would go to it (not trying to encourage underage drinking FYI). The plan works and even allows Fang Yuan to get a huge treasure. Even his enemies admire how magnificent Fang Yang is. Something to mention is that in one of the later chapters, Fang Yuan uses a female Gu Master as a human shield from wolves. However, this was done solely for pragmatic reasons and I feel like it's a similar case to Guts and Megabyte where it's just him being smart than outright cowardly. Furthermore, Fang Yuan is very much willing to take risks and fight tough opponents so I can't say he's a coward.
For being too vile, the OG Fang Yuan has many revolting crimes such as feeding a teenager to a bear and boiling two children alive. However, since the Manhwa only covers part of the first arc, most of Fang Yuan's worst crimes are cut out from the adaptation (BTW, if you're wondering whether the manhwa will adapt those crimes in the future, it's been cancelled for years so that likely won't happen). This version is still fairly vile but most of his crimes are completely tame compared to his novel counterpart.
He does dismember a guard in pieces and put him in a box before sending half of them to the master. However, this falls under pragmatic villainy as it was mainly done to coerce him into giving him compensation for losing 30 Primeval Stones. The fact that the master is impressed by this plan makes me doubt that you're meant to see this as repulsive, especially since the guard was kind of a jerk to Fang Yuan. He has some other crimes but as someone who read the manhwa, I don't think they're particular concerning for the trope. Furthermore, he's pitted against an arguably corrupt establishment at this point in the story.
Finally, he has a Freudian Excuse. Fang Yuan alongside his brother were orphaned and raised by their aunt and uncle who were uncaring for the both of them and only saw them for the use they could provide for the clan. Eventually, Fang Yuan was completely rejected by the clan once he only proved to be a C Grade Talent which heavily upset the teenager at that time. While he arguably moved on from this by the time of his reincarnation, it is clearly meant to give him a level of depth and arguably make him rootable despite being a Villain Protagonist.
Final Note: This only covers the version from the Manhwa and NOT the light novel version so don't bring up stuff like him feeding a teenager to a bear or him boiling two children alive as they don't happen in the Manhwa.