I think we'd rely on the vendor of the load balancer to provide necessary documentation on configuring it before we put it in our documentation as they are more familiar with how to configure their own products. If there's something that our software expects, (for example, setting the Web Context URL for Portal and Server or what headers should be included in any request), then we do our best to document those steps or information. In response to your numbered points:
1) I set the WebContextURL in the Portal and Server's Administrator Directory (from the links above):
Portal
Server
It isn't always necessary to set the privatePortalURL for Portal. You'd only use it if you are setting up an HA Portal or Server can't communicate directly with the Portal over 7443.
2) SSL Certificates likely won't cause a redirect. They have to be installed on any IIS instance which includes the reverse proxy and the IIS instance hosting the web adaptors. They are certificates from our domain signing authority. Even if they were self-signed certificates, they shouldn't cause redirects, only certificate warnings. I'm not sure of the behavior if the reverse proxy machine doesn't trust the certificate that is used for the Web Adaptor machine, so that's definitely something to look into. This can be checked by navigating to the Portal or Server through the Web Adaptor URL.
3) Again, I would refer to the vendors documentation on URL Rewrite rules and Server Farm configurations as it's technically a third party component and not directly supportable. There are a number of blogs on the URL Rewrite module:
URL Rewrite : The Official Microsoft IIS Site
Setting HTTP request headers and IIS server variables | Microsoft Docs
Modifying HTTP Response Headers | Microsoft Docs
The documentation on the Windows site will be far more detailed and will likely be kept up to date more accurately than information we transpose to our documentation.
If it turns out there was a setting or configuration that was necessary to make things work in your environment, then we can consider adding that as a general note, but not include within a larger step by step guide.
In my configuration, I didn't make any changes other than adding the machine to a new Server Farm. I left everything else default.