Pretty... awful... which is to say that it is "pretty" to look at, but otherwise "awful" to play.
Some of the problems can be fixed over time, such as the horrible UI and countless missing features, but the core game mechanics are just not enjoyable, certainly not worth spending much time or money on. It seems as if the people developing this version haven't spent much time actually playing previous Civ games.
The new Ages system breaks the larger-than-life scope that was consistent across all previous Civ iterations into a series of jarring mini games.
The developer says they did this to fix the problem of players not finishing enough games, but they fail to realize that while sometimes we play to win, often we play to become immersed, and don't actually want the game to end because the civilization we built ends too. Creating a civilization from scratch and growing it over time is the core feature of previous Civ games. The process is more enjoyable than the final result. All of that is now gone, in favour of jarring mini game "Ages" that force a major reset at pre-defined intervals.
Overall, it seems this game is designed for casual gamers with short attention spans, but for anyone who likes to become immersed in Civ or other 4X strategy games, this game is not for you. Civ 7 plays like a bad knock-off of itself, or a dumbed-down mobile game version, trying to appeal to the lowest common denominator with nice looking graphics, but offering nothing but shallow and short-sighted gameplay.