General consensus among fans that BD is the worst game in the series : bad voice acting, lots of bugs and generally unpolished game, as if developers didn't care at all, although game has good story writing, funny jokes and even great twist at the end (Rhianna Pratchett wrote the script, with even bigger attention to the game lore then Larian themselves).
Surprisingly enough, the game is very similar to both D:OS and D:OS2, from the BD first OS took two main protagonists system and D:OS2 practically everything else including the story :
Act 1.
* BD : escape from the Samuel's prison.
* D:OS2 : escape from the Fort Joy prison.
Act 2.
* BD : do stuff in imp village quest hub.
* D:OS2 : do stuff in the quest hub on the Reaper's Coast.
Act 3. Some story swaps with the forth act.
* BD : breaking in to the temple of Raan.
* D:OS2 : going through godwoken academy.
Act 4.
* BD : going through Raan academy.
* D:OS2 : breaking in to the tomb of Lucian.
Where I'm going with all of that? If Larian's developers would remake Beyond Divinity as turn based RPG on the Divinity Engine 2, remove entirely battlefields mechanics and improve some gameplay and graphics, expand Raanaar lore, and it's can actually became a great game. Who knows, maybe we could see "Divinity : the Sword of Lies" after that.