Hidden trackable information in games sucks!
I play games for fun and pursuing the goal to win the game is fun! :)
I think Maidens are the only one with income under last dwelling.
No, Yetis, Riverwalkers and Engineers have it as well.
With cheaper dig upgrades, is building all 8 a viable strat
Absolutely. But by no means only for Ice Maidens, for most other factions as well at least in the mid to late game.