If I go up to a 200 yard zero, will I have issues with <100yd shots?
That depends. I missed a deer last year under that scenario. I was set for a 200 yard shot and she came out just 10 yards from the stand. I was considerably surprised as I had never seen a deer that close to that particular stand, I was out of position, and I rushed the shot. By the time I squeezed the trigger, she was 40 yards away and she took off like a scalded ape. After searching for several hours, I went back to recreate the shot and found my bullet lodged in a sweet gum tree. I had shot over her back.
Will YOU have a problem with <100 yard shots? I don't know. Practice shooting at all the ranges you'll expect to see game and learn the ballistics of your rifle/ammo combination.