[Samsung Galaxy S7 Edge (Exynos) ROMs, Kernels, Rec] Christoph21x:
Hi Airbag - thanks for your kind answer. I split my answer into sections.

Yes, they all require root. Except "Autorun Manager Pro" (there are a couple, I use the one of SteelWorks), which can be run on non-rooted devices (limited features). Anyhow, with this ROM I strongly recommend to use "root" with Magisk Manager (you`ll be asked during installation).

Surely not against the rules to ask. No, I didn't try BlackDiamond. It seems to be a good ROM, too, but I have no personal experience. We have several users here that moved from BD to here - maybe also vice-versa. Tip: search for BlackDIamond within this thread, so you might get an idea, why people came here.

Generally a Pie ROM will surprize you - faster, much less battery drain (see https://xdaforums.com/showpost.php?p=79688912&postcount=1129 and following) - BUT: much more parameters that influence this :D . When you install Pie, allow the ROM a couple of days learning phase - it optimizes itself. SOmetimes you will be asked whether you want to activate/deactivate certain functions according to your usage. This shows to you that your S7 learns...

All of your mentioned requirements will be met flawlessly. I did use Netflix on this ROM, too, but not anymore. There is a "Netflix patch" that you can chose during installation, you should activate it.

Magisk will offer you a module that installs an add-free Youtube version - no need to install it (you will be asked) during ROM installation ;)

Yes, there's a "minimum" TWRP version required, if you come from an earlier version of Android: Minimum version 3.3.0.1 - but you'll nearly only find newer releases today - use the latest. What you have to do is to format your system partition coming from an earlier Android version: https://xdaforums.com/showpost.php?p=79731291&postcount=1178

For what concerns banking/payment apps:

I personally have no issue at all. Even not with default (unmasqued) settings of Magisk. I got a warning once when I opened it for the first time - and that's it. BUT this depends on the app.

Fingerprint recognition works fine and very fast. A per-app setting to secure usage is possible (I don't use it though). Fingerprint recognition for banking apps depend also on the individual app, I can't tell, but I don't see any reason why it should fail there.

There's a "masquing mode" within Magisk Manager which "hides" the rooted status - which works for most of the user

Paypal seemed to be a problem to some users (don't know if masquing solves it), but just recently it was stated, that not anymore. And another user posted a solution to those who encounter problems. I personally use Paypal through web interface, not through the app (as I stated in my orginal post, sometimes, less [apps] is more ;) ). Please search through this thread to find it.

During installation of the ROM you can chose whether you'd like to install Knox & Knox-related services. You can simply leave it out. I personally use it as the basic service for "Dual Messenger" services - to be able to restrict access of apps like WhatsApp (eg. to strongly control/grant/disallow access to individual contacts; they're selectable then). As I said: business phone with business contacts here.

S-Health isn't called anymore S-Health but it works flawlessly. I mainly use the mentioned tools instead.

Yes, mine is at 90%. There's a brilliant article about how to treat your LiIon battery (attention: very scientific). AND - there's an Magisk module called ACC (Advanced Charging Controller) that you can install that follows those "rules" and will extend your battery's lifetime (a minimum 2x... some users predict upto 4x). Recommended, I use it for some time now. If interested: read the article to understand what it does: https://batteryuniversity.com/index.php/learn/article/how_to_prolong_lithium_based_batteries

What I forgot to mention: some (quite a couple) users mention that there are problems using the GearVR. As I'm not using it, I can't tell about it. Also some users seem to have problems with AlwaysOn-Display (I don't use it neither).

I'll send you a PM with my contact info for messengers, if you have questions (especially during setup), simply ask. Signal/LINE preferred as you can use them while your phone is offline ;)

Kind greetz - Chris