Rear derailleur cable housing length
It's too long, and you should cut it again to get it closer to the right length.  As a guideline, you could look at pictures of similar bikes online and cut you own cable housing so that the curve ends up about the same.  


If it's too short, the curve is too tight, and that adds friction.  
If it's too long, it adds a bit of friction, and you can get things caught in it when you ride.