Buff idea #2: precognition's hand revelation lasts for more than 1 turn. Potentially the whole game, but the idea doesn't require that
I said that Precognition's hand revealing ability is useless. Did you read?
It really isn't.
Let's suggest you're running an immo rush where you're against any rainbow deck. You have precognition.
You use Precognition and discover that your opponent has lightning in hand. Your hand currently has one photon, one immo, one nova, one golem, and one lycanthrope.
You'd be better off luring the Lightning with the Lycanthrope and then dumping Lava Golem on the table so that you have your best attacker out instead of getting it killed.
Sure, this is one cases out of many, many many, Many many many many where precognition's hand viewing skill is worth it to play around your opponent's strategy and current cards. Hell, I use precognition more for the card viewing than the drawing. I was running a ghostmare a while back and kept using Precognition every turn to monitor my opponents' hand (He was using a singularity OTK.) Once I saw he only had Antimatter and Chimera on hand (the two most important parts of the combo), I used the nightmare on the ghost. He couldn't OTK since he didn't have damage, and I broke the combo there and then.