if i had to rank my favorite Optimus designs itd be g1(mp10 style specifically)/07 Bay>Armada>Star Convoy>Cybertron two of my top 5 being Unicron Trilogy kinda says it all about how hard those designs went as iconic as Armada Megatron is, Cybertron was definitely my favorite look for him of the three. It really sells the more suoervillain type character he is in the show compared to other Megatrons. Not even getting into other cool designs like Scourge, Leobreaker, Menasor, Soundwave etc