You have to do them, because if you don't, the launcher won't let you play.
But most of them for me only take like 5-10 minutes, however, the biggest patch I have downloaded yet, took around 4-5 hours.
I would suggest deleting unwanted files, to give you more space, makes the download quicker, also, fiddle around with your firewall, you have to allow certain ports from your router, and the last things would be to make sure your not downloading anything else whilst you are downloading the patch, and close whatever else you are doing on your computer or laptop whilst you are doing the patch.
Also, it is boring, so if you don't want to waste much time, and can afford to do this, fiddle around with your settings and turn standby off on your computer or laptop, then leave it on overnight, thats what I did with mine, I woke up and it was done, but if you don't make standby off, then when it goes on standby, it will stop downloading, so you have to make sure that is done first.