I have been thoroughly enjoying all of the Incarnon weapons from the original 5 to all the adaptors for those who have unlocked Steel Path.
Personally, I am so happy that Lex is good now since it's one of my personal favorites along with the Boltor and Strun, just because I finally have a decent riven.
Laetum is probably my favorite or second favorite secondaries, very funny with the Glock skin too
I've found the Miter Incarnon most fun out of all the new gun adapters. A lot of them, especially the auto rifles, are very much just "press alt fire to add more damage". I'm not complaining because running around with a buffed Braton is super fun, but it's not exactly anything super special
Phenmor feels the most satisfying to use. I think the animation change to archgun when you go into its Incarnon mode just makes the transition more stark and rewarding. I have a soft spot for Laetum too considering how much I've used it for specific things
I've always loved Sancti Magistar so I'm very happy with the adapter for it. It just gives the weapon a buff so it can keep up with the times. The extra Bleeds on Impact procs is very welcome
The Miter Incarnon form isn't super exciting, it's basically just a buff to the bouncing glaives of the standard form, but the adapter buffs the weapon so much it goes from being pretty shit to very strong. It's like Cedo's alt fire on steroids