Curse of Darkness is an easy transition because it still plays off of Castlevania 3 (Trevor's still there). I think the tough part now would be whether after that you do your own storyline or try to start skipping around. Keep in mind they already completely skipped Lament of Innocence. I also 3 was an easy point to start because it was the first real campaign against Dracula and featured built in side characters. I think it might be best to just role with this crew.
If they do a time skip I'd rather they just skip to Rondo of Blood and Symphony of the Night. Not for nothing but Simon is just a lone man going to face Dracula. There isn't a lot of meat there until the second game and even then it's do some things to bring back Dracula to stop a Curse. I don't know if you can get a cohesive series if every season or two you are just reviving the same villain for someone else to beat them. They killed Dracula early here so they can probably get away with it one time.
To me the best way to do it would be
Castlevania 3: Trevor/Alucard/Sypha team up and take down Dracula.
Curse of Darkness: Redemption arc for Hector with him and Trevor (and likely Alucard who isn't dormant and Sypha who is with him) facing off a two tiered threat of Issac and Carmilla
Finish it off with Sypha and Trevor getting married to continue the Belmont bloodline and Alucard going dormant.
Rondo of Blood and Symphony of the Night: Shaft revives Dracula and Richter must rescue his wife with the help of Maria. Richter faces Dracula but is captured by shaft before he can deliver a final blow so Maria races off to get an awakened Alucards help. You can even play off the early seasons by having Alucard face off against a fake version of Trevor and Sypha.
Then if they really want to continue they can just do Aria of Sorrow and Dawn of Sorrow. Where it's Soma Cruz with Alucard's help. And I probably wouldn't even skip to the present. Just have a slightly older Richter take the Julius Belmont role with Maria as Yoko.
And that's the most I'd do. Assuming they just don't adapt future games with the current trio and do most of their own thing (which I think I'd prefer)