Now there is no complexity growth in block solution task. Without this criteria solutions will become faster and faster. Now bots needs 3 sec to solve a level. With some optimization it will be a fraction of a second. Finally we will came to the point when bot owner will have no aim to share individual blocks among other miners because net lag will be bigger than the block generation time. Bot owners will build series of blocks like 10-100 in a row and throw them into network at once. This is crazy way to go. Complexity threshold should be fixed and tightened to the real time. It should be a race for better and more optimal level solutions.