Very creative use of the theme! Love building as you go and the whole Lego aesthetic, very clean!
I have a couple of critiques, it would be nice if each block had some kind of visual indication of how damaged they are so I know if they are in danger of being destroyed. The bots shooting at you from off screen especially when they have a lot of turrets can feel a little unfair maybe a zoom out could help with this? The last thing is that the UI while very nice aesthetically takes up a bit too much space on the screen it becomes very difficult to see if another vehicle comes from below.
As a suggestion: It could be quite fun if there were random power-up blocks across the map making you want to explore more! Overall though solid idea, enjoyed playing it and hope you had fun making it too! Well done!