Well I am not near as knowledgable as the other guys, but it seems someone missed out on telling you about a BackUp.
I would install Win 10, and Microsoft Office, then do all updates, now make 2 backups (BU). I use AX64 Timemachine (do this one first), then I BU with Macrium (do this one after AX64 Time Machine)
Now install your must have software, but no security stuff yet... Make the 2 Backups like before (This time faster because they will be differential).
Now install some of the security software above, try it...IF you don't like it restore your last BU you just made and install another security package to try...This way your machine is always clean, your not installing security software, then uninstalling it...To restore one of the BU's only tales 30-120 seconds...
Oh last thing... You mentioned ransome protection, if you look at "Cruelsisters" Videos only about 3 or 4 suites/antivirus seem to protect. One was AVG (I use the AVG Suite and it runs very fast on my PC). AVG Ultimate was on sale somewhere for like 30 bucks...Good deal.