I don't think we've seen Shika do too much reactive thinking. Generally things go according to his plans even when it seems like they don't. Again, he has amazing strategy. Itachi has made use of all the people who try to use him and turned it on them even from the grave. Minato, has been the quickest thinker in my opinion. We've never seen him come up with a plan far in advance yet on the spot he's made decisions that save the world 16 years later.Shikamaru does have strategic thinking,logic and anticipation and reactive thinking so he's automatically smarter than Minato and Itachi and as for Obito he's somewhat of an evil genius but ur right about his corrupted way of thinking