I'm conflicted on which iPhone I should get. The iPhone 6 or the 6s?

So I'm planning on get an iPhone for my 15th birthday or maybe Christmas. I don't know if I want the iPhone 6 or the iPhone 6s. I also don't know what color I should get. I really like the silver and the rose gold but can't choose. Its almost my birthday and if I don't choose really soon I'll have to wait until Christmas. Please, what do you guys think that I should pick or should I wait until Christmas and then decide.

What's the best cloud solution for Mac and iPhone?

First of all sorry for my English.

I want to back up my photos and videos.
Dropbox is my favorite but the stock 2GB is not enough, the pro 1TB is too much.
I only need about 50GB so I don't wanna pay for 1TB.

iCloud would be great, but as far as I know, if I delete a picture from my phone, it will be deleted from iCloud too, plus, if I upload something to iCloud from my computer I will have a copy from it in the iCloud folder for local use. So basically I'll have everything twice.
Correct me if I'm wrong.

Is there any other cloud solution which integrates well into the operating system?
Basically I'm searching for a Dropbox alternative but with more storage option.

Thank you in advance!
Once again: sorry for my english.

Why won't my iPhone play music offline?

I know there's the stupid three dot thing off to the side, but selected the make available offline thing for some songs I just bought, and it still won't play them offline! I've never had a problem with this before--just today. And my phone still has 7 GB of storage space left, so I know that s not the problem

How to disable home button on iPhone 6?

I dropped my iPhone 6 in the toilet now the stupid home button is broken. Siri keeps popping up over and over again to the point where I can't even use my phone. I don't have the money to get a new one right now so I need to like turn the home button off. My Touch ID doesn't work either. So if someone could give me clear instructions on how to disable the home button, I would appreciate it greatly. Also I have acessive touch on, so that's why I don't need the actual home button on the front of the phone.

I have a white tiny mark on the back of my iPhone 6 the aliminium part?

Which I want to remove despite it being very small. I try scrape it, scratch it, and rub it off but it doesn't go wot shud I do?

Added (1). I had something similar on my iPad Air but it was sliver and it slowly became into a circle dent. I don't want my iPhone to get a dent

Added (2). Imagine it becomes a dent no I want to sell my phone later on I have to knock off 20-30£

Should I get a 16gb or 64gb iPhone?

I'm looking to upgrade from a galaxy s4 to an iPhone 6 or 6s and I'm debating on what storage space I should get. Is the extra $100 worth the extra storage?

Is the Iphone 5s good for gaming?

What I'm really asking is I would love to play really good yet big games such as free roam games and MOBAs which tend to have a lot of lag and crashes, will these kinds of games crash on an iphone 5s?