"Deepened Pact now works for Hexblade weapons if the Hexblade warlock has Pact of the Blade."
This is not the case. I have made a dedicated thread showing documentation in the Feedback Section of these forums. Please take a look. Both a quick clip video demonstrating and an unedited stream of starting a new playthrough and reaching level 5 with 4 Warlocks, all of different subclasses.