Hello,
I am here to give you the requested critique. I hope you find it helpful and bear in mind that my suggestions are based on my personal views and therefore, you should carefully consider how they fit with your own style before applying them.

Firstly I'd like to say that I'm absolutely amazed by this piece. Its complexity is mind-blowing. Your attention to detail is to be envied. The work shows incredible patience, which is crucial to artists in all areas. Having gone through the walkthrough, I must admit that this is a real masterpiece not only for what it is, but also for its creative process.

Text
I like that the picture has a story behind it and you've done a good job incorporating it into the composition. It doesn't distract the viewer from the main subjects, yet it adds personality to the piece. I tried imagining how it would look like without it but on my humble opinion, it's already a vital part of the image and contributes to the general appearance. In most photomanipulations artists use italics for texts. I guess that makes them look more elegant. You could try with that and see if it looks better to you. I like the formatting - that it's not a wall of text but it's broken into relatively short paragraphs. I think that in relation to the text you need to decide whether you want people to read it or it just has aesthetic value. If the first is the case, then you may want to consider enlarging it a bit to make it more readable. The white colour fits nicely against the sky. Other, more vivid colours would make it look more like a distraction rather than an addition. If you're not keen on the viewer being acquainted to the story then you could play more with the position and font of the text. For example, you could increase the font and repeat it once or twice so that it goes from top to bottom and place it in the right side of the picture applying a gradient so that it fades towards the tower.
Overall, though, I think it fits nicely, that the amount is ok and it's fairly readable (the shadow is a great idea).

Clock
There are actually two clocks in the picture but I'm guessing you mean the one with the pendulum, since it's much darker. On this point I have to agree with your boyfriend - it's a bit too dark and that takes away from its detail. The contrast is not very striking, though. You could try to put some colour and highlights to blend them with the rest.

Colours
The colour scheme stands out even in the thumbnail. The colours are fresh and the tower contrasts nicely against the blue sky. I like the red patches here and there - they add life and vibrancy to the colour scheme. You could add one or two more and see if it adds to or takes from the image. For example one part of the roof that is already dark red could be lighter and more saturated and it may contribute to the overall look. What I find slightly off in this piece is the lighting. There are areas, especially in the bottom of the tower, which appear too dark. Some of the shadows also take away from the detail. While the dark area can pass as affected by smoke, it could benefit from being a bit lighter. Partly the impression of darkness is a result from the light cast by the street lamp. It suggests full darkness as it is at night, while the rest of the tower is basking in sunlight. Part of that shadow is cast by the circular platform but it shouldn't reach the bottom of the tower so it's logical that there should be a visible line separating the area in the shadow and the area exposed to the light.

Overall impressions
I would like to say that the spheres are a very nice addition to the composition. They give the piece a slightly surreal feel so that it acquires characteristics both of the past and of some imaginable future.
One detail that could be improved is the two children. Indeed, they stand out too much, don't blend in well. The colour layers and adjustments make their faces yellow, and their clothes are too light with little shadow. You could work specifically on their skin as well as their clothing. You could select only the skin and play with the colours. Then you could add shadows and highlights on their dresses and hats just like you had done with the rest of the people in the picture. What's nice is that at least it's not a big area. The shadows behind them should be a tad lighter. Shadows in general are rarely black but instead lead to a slight reduction in lightness and saturation of the surface they fall on. You should be careful when using black shadows because there's a risk they’ll look like burnt areas.
On one final note, there are some perspective issues, which could be addressed. Right now what I notice are the stairs just behind the children. There's not much you can do about this particular image in that direction since it would need too much unnecessary altering while it's hardly noticeable but it's good to keep it in mind in your future work. If you want to get into that material, this is a useful tutorial I found: [link]

My overall opinion of this image is that it's very well-balanced, well-structured and meticulously detailed and your work on it deserves admiration. You have managed to put together a very engaging piece, which captures the attention in every aspect.
I wish you to keep improving on your style and keep pleasing your fans with more spectacular work.

Regards,
=drop-asd