Smokin' knows stuff.
I'm no expert,but keeping things simple,taking good notes,adjusting one thing at a time,as you move in the direction that the product suits you,is usually the quickest way to get there.
It also allows you to replicate the successes.
If we try everybodys' recommendations,it is difficult to know how to adjust our process.
The simple way might suit you ,and your friends and family.
There might be one thing that you would like to see turn out different.
Is it critical that the different parts be the same temp?
At this point,all the fine cooks on the forum can probably help get you in the right direction.
My guess is that the places that serve brisket around you,cook to whatever their standard is.
They may cook by time/experience.
They may stick a large meat fork into it,and if it slides off easily,it is ready.
They may just slice the whole brisket and serve.
They may separate the point after cooking,turn it so the grain runs the same way as the flat.
Now,they slice it.
Some may separate the point and use it for chopped sandwiches.
Slice the flat for plates.
Brisket is typically your most difficult to replicate,consistently.
The experience and the good notes get you to your technique.
Your brisket will probably suit you better,after you have cooked a few.
Just my $0.02