While RNG does become a frustrating factor for some things in the ultra lategame, you're also afforded quite a lot of control as you're progressing. For the majority of the play in the post Room 46 bit of the game (ie: the majority of the game) I felt like I had enough RNG manipulation. But then, I also really just enjoyed the drafting gameplay and strategically approaching it in how and where you placed what rooms and how to best use rarity adjustment for rooms and so on.