rohloff
I've got a Rohloff on another bike. The Rohloff is better than a derailleur setup, shifts nicely, is reliable, and I thought it was the duck's nuts until I tried single speed.
I bought a 1x1 frame with the intention of sticking it in. Then just out of interest, I stuck a cassette wheel in and rode it around as a singlespeed for a few days. The virus struck. The cassette was replaced by a singlespeed conversion kit, and I am sticking with the SS setup.
The difference? It's like running through treacle compared to running free with the wind behind you.
You will get stronger quite quickly
