I am not sure what you are saying here. Is Elrond wise because his ancestors were wise? But many of those you mention were gone from Middle Earth before he was even born, and his parents departed while he and his brother Elros were yet very young. Too young to be taught by, or to benefit from the knowledge and experience of his forebearers—unless somehow those were bequeathed to him through the very blood in his veins? Certainly he might have inherited many of their finest traits, like intelligence and courage, but not what they knew "about the enemy's schemes and the secret plans of the Valar."4. His parents were Earendil and Elwing, legendary heroes under the very protection of the Valar.
5. His grandparents were Tuor and Idril, who knew more about the enemy's schemes and the secret plans of the Valar than anyone.
6. His great grandparents were Beren and Luthien who personally battled Sauron and even Melkor.
7. His great great grandfather Fingolfin fought Melkor in single combat.
8. His great great great grandfather travelled from Cuivienen to Valinor and back with Orome.
Let us not forget who it was that actually raised the twins after they were essentially "orphaned." It was Maglor son of Fëanor, who though far from the worst of his father's sons, did take part in all of the Kinslayings, who despite his better instincts and gifts still made many bad decisions, driven by the oath he should have known better than to swear in the first place.
If Elrond had wisdom and knowledge, surely it was not because of those who came before him, but the wisdom he developed and the knowledge he accumulated, through his own experiences and observations once he grew to adulthood. Also, perhaps, profiting by the negative example set for him by Maglor and Maedros.