Need help with GPO and server migration

I am working with a very small domain network, less than 10 users.  I have loaded Server 2016 Essentials on the new box, and have migrated a lot of data and the AD to the new server. I'm migrating from an SBS 2011 server to the new one.  

My issue is that I have very little understanding about GPO, have a few questions. Mainly concerning folder redirection.

I believe that i have setup folder redirection correctly on the new 2016 server, but when I go into the GPM to eliminate the old policy is where i start having second thoughts.

I thought that I could just delete the 'Small Business Server Folder Redirection Policy' but on closer examination I realized that the 'Default Domain Policy' also has a configuration setup for the old folder redirect to the SBS server.   I'm not sure which one of these policies is prioritized first, and how to go about changing this.

So my question is two fold -

First, does the GPO for folder redirect override the default domain policy?  If so, everything I've read says that you shouldn't use the default domain policy to do things like folder redirection, does that mean I should disable this in the default domain policy?  If so, can you instruct me on the how to do this?
Second, once this migration is over, can I safely go in and delete all the Windows SBS policies?  

I'm not at all versed in GPO or very well versed in server management, I'm trying to learn this on my own equipment before destroying someone else's.  I will follow directions and do my best to communicate any further info that might help you.