How do I backup, collaborate, and open files across devices?

Bottomline:

I want to backup my files, collaborate with others when needed on certain file types, and be able to access files from my Macbook, mobile device, or a PC. What cloud(s) do I use?

Current Hardware:

• MB Air
• iPhone 6
• iPad (hardly ever used)
• PC laptop

Details:

I'm having difficulty deciding what Cloud Storage(s) to go with and was hoping I could get some advice from all of you.

I want to be able to backup my main documents folder on a regular basis easily. A back-up cloud storage like BackBlaze could do the trick, but it only seems to backup my laptop akin to Time Machine on a physical hard disk. At $5/month it may actually be something worthwhile regardless, but the main/only functionality as I can tell is the backup. I won't be able to access files elsewhere or share files with others like dropbox.

The next two features that I really would like to have are collaborating on doc, spreadsheet, and presentation files and having the ability to access all files across different devices or computers (with in reason, I know not all files open on an iPhone for example). So essentially this gives me the ability to work on a group paper for school but also be able to open a particular file on my own on another computer at work.

Proposed Solution:

I'm thinking it could look something like this....

• BackBlaze for automatic back ups $5/month
• DropBox for storing my files and accessing them across devices $9.99/month or 99 for the year. But with DropBox one has to upload files individually - royal PITA, so it's really only good if I access it
• Google Drive for collaborative docs. (Free - it wouldn't make sense to pay for this unless I also use it for DropBox like storage functionality).
• iCloud Drive for my photos from my phone. 2.99/month for 200GB storage.

Thoughts? How should I look at this? Thanks!