As this is Altium if you set the layer stack manager with decent dimensions, you will get the proper PCB thickness in the 3D view If 2 layer set the middle for 58 mils and then you will get a 1.6mm PCB thickness. Essential if you plan to export the PCB as a STEP file.
Is this 2 or 4 layer PCB? Hard to see the power tracks for VDD etc, so assuming they are on the underside?
Going by the names of each part you used the sheet design feature so you only had to design the circuit for each stage once. I've used this once in the past and it's very handy for designs like this.