Things to look out for:
CAN connector pinouts should match this image. The yellow line is the edge of the board and the connector is mounted on the front in this case.
If the pad on R2 gets damaged, R1 and R3 are no longer connected which makes losing functionality more likely.
Instead, prefer having traces not broken by pads.
I’ve just placed a GND fill, which means that the GND pads should be connected, but there is still a rats nest showing them as unconnected. This is because I have not re-filled the zones (b), which you should get in the habit of doing as often as you save.
After filling you can see the rats nest has disappeared, but nothing else has changed in this viewing mode (which doesn’t show fills) which makes it hard to notice.
The thing to avoid here is prematurely routing the GNDs that the rats nest shows as disconnected. This looks fine…
But you’re really just routing over a fill and cluttering up your schematic / preventing other traces from using that space.
Additionally: Try not to route on one side of the board what is a fill on the other. For example here I’ve moved the GND fill to the back. Rather than having one big trace and a via, use multiple shorter traces each with their own via.
