Increase of safe areas and spacing to allow for degradation effects
Copper thickness: currently all internal layers are 18um; should they be increased to 35um?
Comments
Addition of another GND connector (like BUSH4) to connect to the earth
Addition of 3rd fiducial on the top-right side
Addition of the guiding element on all the slots in the front between P3 and P4 and on slots 2-9 in the back; the element is mounted on the front of Slot 1, and it is marked as unmounted for the rest of the slots. This will change slightly the routing below the P4 connectors
More even sprinkling of vias
DRC errors on courtyards; are the committed libraries up-to-date? Also should libraries be actually committed with the project?
DRC errors on some tracks being too close, but it is always on MGT length matching meanders, so maybe it's still a KiCad rounding issue?
J24 AUX power connector to be placed on the bottom PCB side
Mark "top"/ "bottom" on the silkscreen
Slot numbers on silkscreen: only the slot index ("1", "2", etc.) is enough to be better readable than the whole text "Slot 1", "Slot 2". Then also a larger font for each index can be used, like for example on the Schroff backplane
Silkscreen box around Power Aux connector on the top side
Via placement for 5_DIFF_{5,6,7,9,10}*, 7_DIFF{5,7,9,10}_* and similar signals introduces little loops, it can be optimized.
A part of the trace of 5_SERVMOD_N, at the right side, is just a tiny bit farther from the group it's routed with.
Comment to reconsider after the thickness of internal layers is defined: The RTM_SHARED signals are 10mil wide, up to ~25cm long and in a internal layers (6 out of 8). Since in the specs [7.1.4] it's mentioned that they could carry up to 0.95A, 4 should be on thick, external layers.
It's not possible to fit more than 2 of them on a layer, so for the other 4, two of the internal layers should be made thicker and the shared signals routed on those should be made as wide as possible.
3 GND-connected mounting holes, maybe the bottom left one is intentionally omitted?
Some mounting holes are also carved in the edge.cuts layer, others are not.