I realize how probably few would dare question God's omniscience, but especially in Sunday School settings there's at least one challenge about that posed to me each year. I won't defend it now. The reason is simply being embarrassed not coming up with absolute scripture support. Many verses declare how God knows all that IS, and of course all that was. He is linked to knowing dispositions while twins are in the womb, like with Jacob and Esau. Well, that is still an IS in that case. Can you show some verses in context proving God allows Himself to know the outcome of every choice people will be faced with? Attempting to come back with a good lesson to support omniscience, I got that study affected by the fact God chooses to forget forgiven sins, so that information is beyond Him forever. He chooses to do that. That alone reduces omniscience, else He really doesn't forget some things. I think He does in fact leave some of the drama with us, all of us often changing our minds multiple times a day. What matters is the final decision so action(s" can be taken. It isn't that God can't know all that, but I doubt He gives effort to retain foolishness day in and out. A benefit of being God must surely be ability to control all your thoughts, casting down vain imaginations, and idle things that are meaningless like how many times I bit down on some gum today. In ministry to troubled people I am presented a lot of awful imaginations and extreme vanity told to me that sometimes are very hard to cast out, being too odd or mysterious. I mull their thoughts a bit to see if there's a clue about what bothers them most, then "spit it out" as quickly as possible.
With His children whose hearts are gladly open to God I believe He delights to fellowship alongside our pitiful contributions of conversation.
Sovereignty is another one. Sure, God could exercise total sovereignty, but then He could be accused by Satan as causing wars and pestilence, etc. He actually gave Adam sovereignty over creation until he sinned, then Satan became earth's lord until Jesus came. Satan's prize was power of the fear of death.