I would like to carry and use a laptop for school, my school has lots of steps, so I have to carry all I have in on my backpack, so I am looking for a lightweight modern fairly powerful machine, it does not have to be the fadstest, but I dont want something too dated, and could handle some light video and photo editing. I also have to ride a bike with my backpack to a bus station to get the bus after classes. I have a 15 inch retina macbook pro, love the machine, but I think it might be too heavy for school to carry in a backpack all day, so am looking for something smaller. which would be better? I also want a good battery life, very important, in classes all day, and cant always get a wall wart to charge.