Well - I played both and I quite enjoyed Heaven’s Vault as well.
I played HV through twice - once for the story and then a second time to see how far I could alter that story with different choices. My wife even played a third time to try for a really particular set of events.
The translation game in HV goes much harder than Chants’. After the first playthrough, you get longer and more challenging texts to decipher.
Also - there’s no backtracking really required. The game is pretty strict about telling you where you can and cannot go and reacting to what you found or didn’t find. You can cut whole plot lines in HV and it’s no problem.
Which makes it one of the better games for replayablity in my mind.