It is, but Dragon Age: Oranges and the Mass Effects (I think... it's been a while) worked in the same way with multiple party members. Sometimes it was fun in Oranges to guide my party around by controlling Dave, my imaginatively-named mabari.
As for departures, Larian have already done that extensively with the Divinity series, which has gone from fixed-perspective isometric real-time to third-person real-time to tactical to variable perspective isometric turn-based, so I certainly won't be making any bets.
Oranges was indeed a fun game, but I personally enjoyed it and it's sequel way more for the story and lore than the actual gameplay. I remember them saying it was a spiritual successor to BG, but then not understanding why I was forced to use the blandly written NPCs with oddly set up stats that kept dying because of poorly balanced damage models and the marginal AI (which was well-intentioned, to be sure).
As for Larian's ability to continue tradition while shaking up the gameplay and style, I agree with their own games it's been effective. With Baldur's Gate, let's just say I'm not holding my breath.