In order to make it easy to later on make changes in my "a little" complex illustration, I keep everything on separate layers. Every item layer group, every lineart layer, every colour layer, on its own. That makes it easy to adjust and correct if I need to. I realise that there will be many layers in this picture, so I will make one separate picture file for each corner, one for the bank corner and so on. Each corner will contain about 15 - 20 layers. The middle with the round about will not be that complex, but still it will be a picture file of its own. The ArtRage files will be 5. The sum of all layers maybe 100! that is why I make separate files not to make it too big and hard to handle.
The sixth image file will be the one with the arrows and text layers (done in Affinity Designer). Each separate "corner file" will then be imported into Affinity as a png and stacked with the arrows and texts on top. After that it will be sent to my editor...