I’m not that keen on Mabon as a festival name. The traditional festival around the time of the Autumnal Equinox round my neck of the woods is Guldize or Goel Dheys in Cornish. This is a harvest festival and involves, among other things, “Crying the Neck”, a ritual in which the last sheaf was scythed and this was usually made into a corn doll. The corn dolls were once kept by the hearth over the winter and then ploughed back into the land for the new year. The traditions practically died out with mechanisation and modern farming techniques, but fortunately were revived and saved for posterity in the early 20th century.
The reason that I’m not so keen on Mabon is that the name for the festival only originated in the 1970s and the mythology of the relatively obscure figure Mabon ap Modron does not really have much to do with harvest traditions. Now, if people involved in Druidry want to celebrate Mabon, that is their choice and I hope they find it rewarding and fulfilling, however, I personally find it far more “organic”, for want of a better word, to keep up the country and local traditions of the Celtic nations because those, in my opinion, are more of a living link with our ancestors than anything else.