I like the way you think, markyboo - along those lines ... how about a twist on the Josette/Barn/Angeligue triangle?
Barn as you suggest, feels an immediate kinship with his modern family. He is taken by Vicki's resemblance to his Josette, but struggles against his desire to try to turn her into Josette.
Julia arrives investigating the pathogen found in the wounds of some assault victims found "with throat trama." yada yada and so on "I can cure you." Basically the Julia/Barn cure plot but the Angelique has resurrected herself or found a way to travel to the present to ensure the curse continues, puts willie under her thrall and through him doctors the serum. vicki begins to have strange dreams and sometimes believe she is Josette. Basically, Ang is simply trying to drive a wedge between Barn and the new found family and acceptance. If she can cause the kind of mayhem she did in the past then he will continue to suffer.) But, Barn turns the tables on his old love: reveals that he did care for Joestte, but he was always in love with Ang. However, the destruction she caused (sarah, his mother Jeremiah, and so on) have killed any passion, any love he may have felt for her. The spell that holds her spirit to the modern time is broken and she vanishes into the past (or departs the hapless Collinsport ressie she possessed - Carolyn perhaps, or Maggie).
Meanwhile in the B Plot - Vicki, who was hired as governess to troubled David by mysterious recluse Elizabeth, has come to try to discover her past. She is considered familiar looking by most of the family but they cannot place it until cousin Barn comments on her resemblance to Josette. Elizabeth is troubled by how vicki (an apparent complete stranger resembles an ancestor) Of course this is the plot fans have wanted to see for decades but while strongly hinted there is no revelation that Vicki is a Collins.
In a flashback, we learn that unbeknownst to even Ang, Josette had dallied with Barnabas and was discovered to be with child. The whole thing was hushed up and Natalie and none the wiser Ang sent to Maine while Andre and Josette lingered just long enough to make things respectable, and bring Josette to Collinwood to marry Barn. The child would then return with Barn and Josette after an extended honeymoon. So there is a suggestion that Vicki could be Liz's daughter or that she is a descendant of Josette and Barn's love child.
Okay that is a little disjointed that is kind of what I would like to see: The old classics (Julia in unrequited love, barn and and and josette, the vampire cure plot that goes wrong, Vicki/Liz), but new stuff also - the toying with the 1795 relationships, love child, the revelation that it was all for nothing because Ang had won until she destroyed his family, and earned nothing but Barn's contempt.
This would just be the first film: Characters introduce briefly here would be fleshed out later - perhaps the Roger David problems as the B plot in a future fim, Barn is actually cured, perhaps Chris and/or Quentin as as werewolf and of course ang could return. Even Stokes could be given a more sinister bent (not evil, but perhaps much more sinister).
Of course time travel would be a natural vehicle for a film as well - something goes wrong in the present that Barn and Julia have to return to the past tor correct.
okay, I've run out of steam .......