Currently I am playing it and the way I personally feel tht this game was designed is for players to do every quest, location discoveries, and objectives in the regions the main story takes u through.
(I don't know whether this method will work for u but try and think tht u r having fun while playing and slowly u will start enjoying it as u play)
I finished Siwa, and Lake Mareotes regions and I am currently in Alexandria at lvl 14 doing side quests and other stuff. I have the three main quests, Aya, end of snake and the genadios quest left to move on with the story. to me tht think and play method is the perfect way to play such kinds of games, without getting bored and frustrated. so yeah it may or may not work for u, but I suggest u try it anyway. good luck.
@Andrej997 yeah i enjoyed it but i totally understand who dont like it. Heck even after that massive grind i wanted to take a break because not long after i completed origins odyssey got released and i still havent started it yet.