To start with, the presentation of the subclass is beautiful. The cover art is eye-catching and stylish, very impressive and comparable with the alternative cover of the official WoTC books. And the other art piece used is thematic and very fitting as well.
As for the Paladin itself, it has a clear, very compelling theme, with which creating a cool character will be very fun. Furthermore, on the mechanics side of thing, the Oath Spells chosen for this Oath are thematically appropriate and also very useful. The class features are creative, fitting of the concept, balanced and appropriately powerful.
I'd allow this Paladin Oath at my table.