[nijave]

For background transfers reducing processing time can also maximize sleep/low power mode, too (Doze is one of them on Android but I think there's some other low power states)

There's some interesting (imo) research about optimizing cpu governors on Android that details some of the tradeoffs (like running high power on a single core might be better in some cases than longer at low power if the core can be hotplugged/disabled sooner)