I'd like to second this request. I've started using Affinity Designer to prepare scientific figures for publication and often have multiple elements that I need to turn on or off - text, figures, data, etc. independently and use layers for this. However, I also need to be able to move all these elements around to different parts of a figure and in Illustrator I was able to group and ungroup and retain the layer information. In Affinity, I must re-direct everything back into layers. I would really like to have the option to keep the layer associations persistent regardless of grouping.