There is a popular trend in crochet that is making the rounds. It is called Corner to Corner Crochet. It will allow you to complete larger projects in a lot less time. It produces an eye pleasing texture and allows you to do diagonal stripes without constantly changing your yarn.
Below is a good tutorial on C2C by The Crochet Crowd:
And here is one from Red Heart:
And here is some examples of completed works in C2C by Babbling Hook Creations: