How many angels are there in Revelation 14?

While this passage is often referred to as the "Three Angels' Messages", we're looking at the second half of the chapter which only starts after those three messages have been described. Additional angels continue to feature, with further messages! It does seem strange to be working backwards through Revelation 14, but there's a valuable discussion about the "Son of Man" character in this part of the chapter. We also ponder the idea of harvest and being "ripe".