RNG to get a good item you need. RNG to see if it corrupts. RNG to see if it is a "good" corruption. And then more RNG to see what level of corruption it is.
Wasn't the whole idea to make a system better than titanforging?
This is the kind of thing that has me concerned about Shadowlands. I don't think Blizzard lacks the ability to create interesting things. I think they just really don't want to and don't care. It's not Activision, it's everybody at that whole company, they just follow metrics and design everything around Skinner box ideas and making players play for as long as possible, while creating as little content as possible.