Edit 2: Just remove this, this Forum is not friendly at all.
Maybe I'm misremembering but i think I replied to this thread with a comment meant to be funny (a quote from the old Red vs Blue cartoon series). But it looks like my other comment is no longer here, indicating perhaps that it was deleted for seeming off-topic. Apologies if this made the forum feel unfriendly; that was not my intention.
Because of the thread title, when you said, "Timeline of Warcraft," I took this to mean that you are asking if you should include notions of the Blizzard/Activision/Microsoft timeline in your story. Partly by replying with a now-deleted joke, I was also meaning to express my exasperation at Activision. Because, when you say,
(Taking into account that I'm pretty flawed in terms of timeline etc...)
... certainly my understanding of the "official" Warcraft timeline is extremely flawed. I guess there were two planets, one with humans and one with orcs, but then the orcs were visited by space demons who fly around in spaceships, but instead of using their spaceships to fly to the human planet they used magic to open a portal to the human planet. But they used too much magic, and it destroyed the orc planet. On the human planet, the space demons had exploded Pangea into multiple continents using magic 10 thousand years ago, but in the present day they decided to come on back so they warped in their leader using magic, who then got killed by orcs and humans and mutant trolls working together via a trap they set up using a tree that grew from the waters of Pangea. Unfortunately, before he died, one of his minions reanimated an orc's soul in a block of ice in the arctic, who then tried to take over so he could overthrow the remaining space demons and rule the world for his own fun. But unfortunately, the reanimated orc soul was actually being manipulated by the tentacle body horror monsters from under the ground, who are older than the space demons and have existed since the dawn of time. Although the creature of a thousand eyes was killed in the desert down south, up in the arctic the creature of a thousand mouths was still alive, manipulating everyone and manipulating the reanimated orc soul. While everyone was trying to figure out what to do about it, a corrupted dragon flew over and landed on top of a stone wall the humans were building, which made them really upset. So everybody chased around the corrupted dragon and killed him for being too powerful, and for knocking down their stone walls. While they were chasing him, they discovered a mystical island shrouded in clouds where the pandas and pokemon lived, and so the orcs and humans decided to continue their war on the panda island. But this angered the gods who fund the universe, who wanted a story about orcs and humans rather than panda and pokemon, so the god of time created a portal back in time to when the corporate stock price was higher, unleashing a new war between the orcs from the past and the humans from the present, because the orcs from the past hadn't learned to cooperate with humans from the present yet. This time portal caused the evil orcs who destroyed the orc planet before dying to be alive again, by usurping the time portal to come back to the present. At this point the evil orcs from the past teamed up with the space demons, who attacked the human world with their spaceships directly. Then an undead elf who had been reanimated by the reanimated orc soul was feeling really angsty and burned down a tree, then went to the arctic to kill the reanimated orc soul once and for all, but it had already been replaced by a tired old man. So she stole his helmet and ripped it to pieces, opening a portal in the sky that would allow everyone to travel to heaven and hell in the afterlife. And it was there, in the afterlife, that everyone gathered together to take back the infinity gauntlet from Thanos and save the world. And about that time I stopped following the official timeline -- or maybe I never followed it at all.
This is my exasperation, and my inability to properly express it is my way of saying that I think you do not need to include the official timeline in your creation. I think it's better to make good gameplay, and hint at storyline when the storyline fits your gameplay. If you go too far out of your way to do dog-whistle to the imaginary audience who want the timeline to be real, you'll end up chasing nonsensical loose ends instead of just having fun.