Just going to plug in my 2c here.
First, you are spending a lot of money on a new machine, spend a tiny bit more and get a full version of windows 10 rather than cheap game out and getting oem version. Why, well you have a perpetual license then, which you can install on any machine/setup. Oem tends to be limited in various ways.
Now, hardware, I have a 500gb ssd with win 10 and a few apps installed, I keep it nice and slim and clean, only install what I need when I need it. All the apps on here point to a data drive (say musicbees library) which is 10tb. External to the computer I then have a raid 5 box with around 12tb space, this is a direct mirror of the internal drive around once a month or sooner if I have created more data. Next I have another raid 5 box external to the house which is a mirror also. Finally I have an older external hdd which is a long way away, fixed timepoint save.
I don't clone out the os, what's the point with a full licence and all my apps ready to restore from external drives, in fact hat a good opportunity (that once in 5 years or so) to start a nice fresh install - those of us using it for many years will likely still be in the habit of re-installing windows every so often as it seems to be impossible for m$ to clean up their own os correctly.
With regards to online storage I do not trust it at all. Both from a point of view of people getting acces to it (don't know if those who used mega ever got their files back?), or from a point of data mining. Your in the us so I don't expect data privacy is even in the dictionary, so bear that in mind.
Final thought, always get a drive/raid or whatever backup a lot bigger than you think you need. Space really fills up quickly what with high quality film/pictures/music, games etc.