Here too, I have built one army in 1/72 before I knew better, then half a dozen in 15mm, and one in 6mm. However, I am interested in the 100 years wars and wanted to do it in 6mm. According to Pete at Baccus, he will do them in 2021. So I will be waiting, however, meanwhile, I have decided to do both sides in 10mm with Magister Militum and Pendraken figures.
Oddly enough, I don't like all that much when my figures are packed on a base (the "mass effect"). For 10mm, I am just planning to add 33% more figures than at 15mm scale. So a 3Kn will have 4 cavalry and 4Lb will have 6 Longbows. At 6mm, I just double the number of figures that are usually put on a base at 15mm.