What are the biggest 2-3 issues with this level (given the creator’s goal)? Importantly, why are these important issues? We care less about what you think is an issue, and more about why the creator (yourself) should care about an issue. Not everything will be important enough to spend 30 hours on fixing it.
Main issue is I am not getting much of a city theme from the level, it looks just like a nice effect level, but the city aspect is completely untouched to my eyes. 4 minutes is also a huge committment at that level of decoration so be sure that you are mentally prepared to go through that.
How would you solve these issues? For this question, make suggestions that directly address the problems you stated. For instance, if you say the level’s colors are too dark, your solution should make the level brighter in some way.
Either the block design or the background should be changed to reflect a city more. Maybe add more windows to the block design or have the background shards glittering behind passing buildings instead of being unobstructed. Maybe shift it down to two minutes, see how you feel, and then add more gameplay/decor if you are feeling good about it.