Restomod or Original OEM style?? - Feedback Appreciated!

Personally I would skip the power brakes, a properly set up manual disc/drum configuration provides plenty of stopping power for these light a bodies. My brother has a 68 Dart GT with power disc/drum brakes, I had a 70 Dart and two 75 Dart Sports, all with manual disc/drum setup that worked as well or better. You could add rear disc brakes if you want to increase the stopping power without the loss of space under the hood for the booster.
That 68 Dart GT has a 318/727 combination with aluminum heads and tips the scales at 3300 lbs.

Just my .02.