For what's it's worth, this video from a German magazine (and currently only in German, but earlier ones got english subtitles) is pretty close to a review (at current state).
They see lots of things to improve but praise the freshness. They specifically recommend that people shouldn't shy away just because they dislike switching - of which they themselves don't seem to be too convinced - because they would otherwise miss a very good and interesting gameplay experience.
I'm not going into the "good" parts because those are mentioned often enough in all previews.
They note that many of the present issues are not where they thought they would be - at the ages and related stuff. Instead, they noted:
- AI is often (but not always) too passive
- Yield inflation would be problematic (like in Humankind)
- Too many buildings with similar effects
- Balance would be off, but somethings could be improved even until launch
- Onboarding is bad and follows an outdated concept: it relies too much on the civilopedia and hides too many things from players
But they also note age-related issues:
- Techs/Civics towards the end of an age are relatively useless, because you have hardly time to make use of the unlocked things
- Resetting wars and IPs at age transitions make for strange interruptions
They claim that the success of 7 will rely on 3 things:
- Fine-tuning onboarding and balance
- Inclusion of a fourth (post-modern) age in a free update instead of an expansion
- Whether players are willing to accept so many novelties