Actually, as of the series finale, Quentin is the only immortal. Angelique, when last we saw her, was a mortal woman again. Barnabas was no longer a vampire. Quentin could easily have gone off somewhere to not explain his aging. He's done it before. Maybe he's had plastic surgery, even!
The advantages I see in TNG approach is that it is a polite and respectful nod to the original fans without getting bogged down (at least not too much) in former continuity. Frankly, a few flubs that way are to be expected. TREK did it. The original series did it all the time. With a little care those can be kept to the minimum. On the other hand, many of the iconic things about DS would of necessity go by the wayside. No Barnabas/Josette/Angelique triangle. No Julia Hoffman.
A true re-imagining gets around that, by pulling a BG (Battlestar: Galactica). Or if you will, imagine the story as another thread of Parallel Time, another continuity altogether (like Marilyn Ross's novels). Then you can not only tell an old story in a truly refreshing way, but put upon elements from all of canon--not only 1969 but 1895 and 1797 and 1840. Among other things, this might mean more members to the Collins family. Quentin might be Roger and Elizabeth's brother. There might be a branch of "poor cousins" who live in Collinsport. Etc. Etc.
"Zahir" btw is my dance name. A former girlfriend of mine was into Middle Eastern Dance. She got me into it, and I found it was a lot of fun. Traditionally, dancers (usually but not always) take "Dance names" to perform. Zahir is Turkish for "the blooming flower" (the feminine version is Zahira). My given name is David.
In other words, I am a male belly dancer. Yes, there are such things. No, I do not dress up like Barbara Eden.