So far, I've come to the conclusion that my MC will be OP in the sense that he can contend with the strongest beings of that world, or at least hold his own, but he can't just wreck them and he certainly won't be conquering "the world" anytime soon. I would liken it to being Superman. Yeah Superman is strong as hell in every aspect of the word, but even he gets his ass kicked often enough for everyone to know that while he's one of the strongest, he has worthy rivals who could stomp him into the ground if he gets cocky and overconfident and thus he can still find room for improvement.
As for story, will be going the Overlord approach as mentioned by
@Jemini Meaning there will be a large and active cast of side characters, as well as a small group that I would liken to being the MC's whenever the Main MC isn't being used.
Momonga from Overlord who was probably the main POV for like....the first 3 volumes, and then every volume after that, he was just one POV among several, and he didn't even show up at all as a POV in a few of them. Or like Wheel of Time, Rand was the main POV for the first 2 books, and then from Book 3, he was just one among many other POV's, and in at least 4 of the books, he only showed up in 1 or 2 chapters. In one book, only the epilogue. The only book Rand was by far the dominant POV besides the first 2 books was the very last book where his POV took up the entire second half of the book.
I'm not sure which approach I will take, but I'm more likely to go the Overlord way, since side characters were more prominent POV-wise in Overlord than in WoT. Hell, several side characters dominated their own entire arcs, with absolutely no interference from anyone from Nazarick except for perhaps in the background. I don't think it would be Game of Thrones style, since while they had a large cast, most characters tended to have only 1 to 3 chapters apiece per novel except for Jon Snow and Daenerys and I want more active side cast than that.
Also, my story will basically be a rewrite of someone else's story here on SH and RR. They have gotten to busy to write it and I loved it so I decided I would take it over with their permission and do my own spin on it with the greenlight from the original author,
@Discount_Blade