Hi MEB,
I have been watching this thread since it started, because the lack of this particular feature is what is preventing me from switching from illustrator to Affinity.
I understand the small team issue, but we have been waiting for three years, and this is essential for people who import vector files that were created elsewhere, for example pdfs and just about any output file from GIS software. Exports always come with totally screwed up layers containing hundreds to thousands of objects, and being able to select objects by stroke and color is the only way.
We are planning to get the Affinity suite for our entire department (staff and students), but we will not be able to switch from Adobe until such a feature is implemented.