I use Win 10 essentially with traditional 'desktop' programs- I don't use
- Cortana
- the Win 10 start menu (for very good reasons)
- the package of universal apps (Mail, games, Photos, Groove (music) etc etc
I use the free Classic Shell start menu- which behaves very sensibly in a way familiar to Win 7 users. Hey, I even have a Win 7 Orb.
I find Win 10 stable- can't recall a crash or BSOD.
But always act defensively. Use disk imaging. Be prepared.
Pro doesn't give you greater security unless you count Bitlocker or trusted boot. It does give you a few features.
Windows 10 Home vs Pro: What Extra Features does Windows 10 Pro have? - PC Advisor
Windows 10 Home vs Windows 10 Pro: the key differences explained | TechRadar
It can be useful to have the group policy editor available, as then the corresponding registry keys are also available. Some tutorials here specify they only apply to Pro upwards.
Pro offers more control of updates, including the ability to defer feature updates. In the Anniversary build (current, being upgraded to the Creator's build) one can defer build upgrades for months. I understand this is much reduced in the Creator's build.
Some have struggled with unexpected restarts related to updates, a very bad move on MS's part. This can be controlled- group policy settings and a 3rd party tweaker which uses those help- and the latest build offers more control of that. So beware.
MS has had a habit of bringing out a major build with which some have had various difficulties- and in the Creator's case, all with certain 'under the hood' aspects, and then bring out 1 or two updates in the 2 or 3 months following to fix that.
Comments about Windows 'spying on you' with Win 10 are somewhat like urban legends. Yes, statistical data is sent back; it's not personal data. Heck, your ISP spies on you all the time, if you look at it like that- so don't use the internet. So does your mobile phone company. Hmm.
You can disable some of the reporting/monitoring aspects quite readily.
Some with older PCs have difficulties finding compatible drivers.
It is true MS is pushing 'standardisation' hard - a common platform across supported devices with much less flexibility in theming and appearance. But there remain ways.