The way you describe it sounds like a frustrating system to me. Depending on the rest of the game, it can range from no one using potion making, to completely ruining the game.
For example, solving a crossword is fun, because there is a challenge, they give you a clue and you must use your intelligence to solve the puzzle.
Now imagine a crossword puzzle, where there are no words or clues and you simply have to place letters until you get it right. Do you think it's fun? Is there a challenge? Is there motivation?
As @Afloof.dev says, you also have the balance problem.
"The idea is to challenge the player in a captivating way" A random map can be challenging, because you have to think about how to adapt to a different map (challenge), but in potion making, if it just comes down to trial and error, it will just be boring. .