These ideas tend to not work out that well, as the main cost-factor is often the bus-driver and increasing the frequency means hiring more drivers. I also think bus driving isn't exactly an enjoyable job as it can be quite monotonous, so increasing the number of such jobs is probably not such a great idea.
What might work to some extend is some sort of shared but on demand mini-bus taxi service, and of course potentially self-driving mini-buses, but really ultimately there is little one can do to solve the fundamental transport issue of low density housing in such suburbs.