All three options are fantastic. I like Khyber's spell capture shenanigans, Eberron's unlimited magics, and Siberys divination and meteor summoning. All of them look very fun to play, but also balanced at the second thought. Highly recommended!
Really flavourful. Perfectly explains how they fit into the world of Eberron and what ways you could be getting the pact. The Enemies and Allies section is incredibly useful to the player when choosing the pact an the DM for making the campaign interesting, wish all warlock pacts had something similar! The fact that the author also made their own art for all the pacts shows the ammount of love they put into this. Highly recommend