I've not played a lot of these games, but it was primarily Kings of Chaos. Different factions with different bonuses is pretty cool, and I always chose dwarves due to being a very defensive player. So an idea to fit your theme is something like Italian family, American family, Bosnian family, or something like that?
EVE Online has the best player-based economy imho, and I think an economy like it where anyone can contribute and benefit is pretty cool, even cross-faction.
To mitigate cheating/macros/sweaty players, I think there should be either some timers to actions, but this is an incredibly fine balance to not turn off players' engagement. A puzzle/mini-game to grant additional free resources can help the casual players to remain engaged, like how Kings of Chaos had a captcha for recruiting (userscript was used to speed up the process, and become the unofficial standard), and EVE Online had the "analyze the signal" kind of mini-game that yielded ISK.
I think the amount of time to be spent when you log in should be generally limited to about 10 - 15 minutes. You heal, recover from attacks, buy new upgrades/restock, and then do things like initiating an expedition, spend your available resources, and then let it go like 8 - 24 hours before energy and such are filled again.
Player interactions are important, and being able to make either one time deals or recurring deals that involve something like "If you attack my enemies, I'll give you a bonus/grant you equipment" or "Whenever I'm attacked you will spend 20% of your defensive capabilities to add to mine" etc. And of course with simple trading too.
A "vacation mode" like the one Kings of Chaos had I think is very important, that essentially freezes all your passive gains and progress, but you are made immune to attacks and sabotage (making a manual progress-action requires you to disable vacation mode).
Risk-reward should be available in all tiers, to cater the most players. E.g. low-risk expeditions where the gains are low but steady, not reducing or resetting progress, and high-risk stuff that could potentially cripple your enemy, but could also cripple you.
And of course, have a solid mobile interface, as that is likely where you'd get the most traffic these days.
I hope my feedback is good, and I wish you good luck with your project!