I believe that time travel is not a good idea.
Think of it this way.
If you go forward in time and you discover new things, good but you could always screw something up in time.
I mean, you may watch Futurama, my favorite show, but in all reality.
IT is true, this could be a good thing, but it could not be at the same time, you could go back in time and change history for you to be the overlord. You could do so many bad things, but also good.
The pros and cons in this are so high I can not name them all. There are so many.