Underlying mechanics are sound?!? You having a laugh?! Terrain is extremely imbalanced (hills=king). Military balance is out of whack (melee is junk-tier) At least 3 of the economic inputs (food, hammers, and beakers) are out of whack (hammers god-tier, science worthless, food mostly worthless). Civics range from completely worthless, to insanely OP. Same goes for the Civilizations/leaders; we've got some with obviously broken combos, and others that have so little synergy with the mechanics of the game that it makes you wonder what they were thinking. Religions is just buffs. The combat aspect is mono-dimensional, and thus tedious & boring. Culture/Tourism is an enigma to all. Many of the wonders aren't even worth sacrificing a city tile for, let alone spending hammers on them!! The mechanics as they are right now favour one thing; Domination. Make an insurmountable army->go on the war path->upgrade as you go->win the game. There is absolutely no mechanic to inhibit expansion through conquest (and/or stealing workers/settlers). In my book that's a MAJOR flaw. However much I hated civ5's global happiness (give me back civ4's city maintenance any day!), civ6's amenities system is not a suitable substitute. Its fundamental flaw being that your conquests will by-and-large be self-sustaining, either because of their own districts, or thanks to the new luxuries their land gives you access to. There are other factors that result in unimpeded military expansion too: cultural borders are static & immediately inherited by any captor captured cities have no unrest, and besides damaged structures and paused growth, instantly become 100% productive members of your civ. More begets more.