Doesn't sound too bad a reasoning. However the only time I've ever done any of the BG anticlockwise was supporting Full Moon Addict on his winter BG so may not be the best person to ask!

My usual aim with picking the night section is to chose that ground where darkness has least effect which tends to mean either ground that you can maintain pace on in the dark (i.e. roads and non-technical fell) or ground that is rough enough to slow you down even in the daylight, which for me is the heathery stuff in the back of Skiddaw.