All of the maps require awakened units (Not necessarily a full team. But it can help). A maxed black unit would fall short, as well. The only two I have yet to do myself is spirit rescue and demon crystal. I'll likely do them when I build a team for those maps when I get around to it. As far as I'm concerned, the only reason to do G maps is for more gold on mondays (not sure if thursday daily has increased drop rate). Affection items and spirits can be obtained any time from challenge maps.