BaK is certainly a cool game and was lots of fun at release, but I'm not sure what point there is to a "spiritual successor". It was essentially an interactive novel -- in the era before real cutscenes, BaK had massive blocks of text and dialogue that ran by on autopilot while the player, left with zero control, simply watched.
It was more than interactive novel - it was integral part of the Riftwar saga. Half the charm of it was going to familiar places and meeting up familiar people. It hit a golden spot between games set in modular worlds, where nothing that happens therein matters shit anywhere else in the setting (like all the D&D, Star Trek, Star Wars etc games) save for a maybe occasional cameo mention, and strict novel adaptations (like all those LOTR games throughout history) which universally suck balls as games. BaK had an artistic freedom of being a brand new story, yet firmly grounded in Riftwar canon as a direct sequel to "Darkness at Sethanon".
Hence the Antara mention - I haven't looked at the credits, but it was a carbon copy of everything BaK all over, except with a new setting and unfamiliar characters tucked inside. We all know how it ended up.