Coming together but . . .

the spindle hangs a long way out in front of the gantry - what's happening with the Z axis? Can you show a side view of the Z axis ? Is it profile rails on Z - looks like they are very close together and possible you are not pocketing the ballscrew etc. therefore giving large overhang.

Stiffness drops off significantly as you move out from the gantry so worth getting it more compact if possible.