First, a few specifics about dead and absent Elders. Oberon is dead, Brand is dead, Eric is dead, Dierdre is dead. They're really genuinely dead. There's no point in assuming that they're behind everything you can't explain... that would be like my blaming my inability to balance my checkbook on Hitler. Just thought I'd mention it, since "Brand Did It" appears to be a common theory. Don't even get me started on Osric and Finndo.
Corwin and Benedict are absent. Like, gone for years and years and Lyr only knows where their bones may lie. Merlin and Dara are absent. If it were possible to casually go out and find them, somebody would have done so already. Heck, somebody might have done so already, but if so they didn't mention it.
Now, on to the active Elders at large. I've only got a little bit to say about them as a class, but I consider it important so perhaps you'll humor me. Remember that the odds are good that any Elder saw your character in diapers, and helped them learn to speak. This is great if you're trying to manipulate them by playing to their nurturing impulses. It's really not so good if you're trying to threaten, blackmail or otherwise frighten them. No matter how much the kid I baby-sat in my youth has grown, it's always a little hard to take him seriously. Same thing applies. Those who realize this and use it to their advantage prosper. Those who don't... don't.
It is possible to convince your Elders that you are now a mature individual, and that they need to take you seriously, even be frightened of you. But like all important things in the game it doesn't happen all in an instant. It takes time.
The best way to start on convincing an Elder to treat you like an adult is to actually work with them on any of the various things that need doing to keep Amber and its trade Empire running smoothly. Most Elders will be very active mentors if given a chance. Yes, they may manipulate you a little. Yes, they may deliberately put you in horribly dangerous situations, just to see how well you handle yourself. But they won't bore you, not if I can help it.
The Family... there was Oberon, who ruled for centuries past counting, and before he died he sired a brood of brilliant egomaniacs, all intent upon proving themselves better than anyone and anything, most especially their own siblings: your Aunts and Uncles.
All of these are of note: They are the shifting stars of the constellation of Amber's power, and they are the road-blocks that will occasionally stand in the way of the PCs as the younger generation begins to rise to their own equal power. Even those who are dead and gone are important, for their memories inform the actions of all those who remain.
Benedict: The acknowledged greatest swordsman and general of a family that would acknowledge NOTHING that he had not proved time and time again. The ultimate warrior. It must have been so wearying, to be the best and not to have it make a lick of difference. He has not been seen in Amber for over a century, and those who try to find him return empty-handed.
Bleys: Brilliant and flickering as a flame, master of sword and spell, charming, gallant and always ready to explain why he has only your best interests at heart. Bleys is well known in the Family for his insincerity... not for lying as such, for he takes a certain perverse pride in not needing to tell direct lies, but he says whatever he says for a reason, and it is very seldom the reason he claims. He has proven the most adept at living with the many contradictions of Random's rule, and is one of the three most closely in the King's favor.
Brand: The lunatic, villain of every history, the man who went further than any of his siblings to assuage his own ego. This was a man who would not merely allow the universe to fall rather than fail to rule it, but who actively struck it down on the basis that he'd be able to name his own price for saving it. He is SO dead. Seriously, no smileys. Don't blame him for your troubles, he's too dead to have caused them.
Caine: Dark and cynical as Bleys is bright. Master of the seas and of spies, Caine is always ready to explain that nobody has your best interests at heart. Caine does not pretend to be a good man, and does not tolerate well such pretense in others. His ability to bluntly say and do what others shy from has served him well in recent years, and he has risen from earlier obscurity to become one of the three most closely in the King's favor.
Corwin: The other lunatic. He is the one of the family who can best think the unthinkable... who can love freely, not counting the price of betrayal, hate unreservedly not counting the innocent lives he destroys. He has been gone so long that most people assume he is dead, but the mere mention of his name can still put any of the Elders on edge, glancing nervously over their shoulders.
Dierdre: The mystery, little spoken of though always with reverence. She died at Brand's hands, but there is always the sense when the Elders speak of her that she did so with intent, deliberately, that her sacrifice was something that had to be done.
Fiona: The unrivalled mistress of sorcery, of secrets and hidden knowledge, and of manipulation. Fiona is always ready to explain to you why it is in your best interest to do what she wants you to. However, her arrogance is undiminished by the centuries, and recently it became her downfall. She fell in love (or at least claimed to) and had a child... and then thought to subtly trade upon the familial feelings this provoked in order to rise to a position of unparalleled trust at Random's side. She failed. Though she is still Family, still given every courtesy, it is clear that Random intends never to trust her in anything again.
Florimel: Of all the family, Florimel is the least inclined to resist. When pushed she retreats, when pulled she follows, and yet there may be something in her fluid and unassuming nature, for she is always close to power, never cast down and disgraced like all of her siblings have, at one time or another, been. Florimel is always ready to listen to you about your interests... but what is "best" for you? On that she keeps her own counsel. Her ability to sniff out the best side to ally herself with on any issue is unchanged, and she has become one of the three most closely in the King's favor.
Gerard: The strongest of the family, Gerard is also widely regarded as being the least shrewd, the least calculating. When he says something, it is trusted as truthful. Of no other Family member can this be said. He is always ready to tell you where his best interests lie, whether they lie with you or not. In recent years he has espoused a curious (for this Family) interest in actually doing the right thing, even to his disadvantage. This has brought him into conflict with Bleys and Caine, whose position he rivalled once. Now he is... less readily listened to. Not disgraced, but shuffled down to a second tier, at one remove from the center of the court. Here he jockeys with Llewella, who has risen from disgrace to this level, and hopes to move further.
Julian: In a family where most personalities seem to have calcified with the centuries, Julian remains curiously flexible. He is actually changed by the actions of his siblings, in ways that they don't often seem to recognize. You can tell instantly upon meeting him that the man they describe from the memories of their youth is not the man he is now. As to what he is, that's much harder to say... he's not advertising. He is always ready to tell you off when you deserve it, even if it's to his disadvantage. Praise comes more rarely. Still, his family sees him as they learned to see him. Random, particularly, clearly still views him as Eric's thug, even after all these years. He is in disgrace, and probably will be for the indefinite future.
Llewella: Increasingly, as time goes on, Llewella has come to be seen, if not in direct opposition to Random, than certainly as a sharply delineated alternative. Where Random leaves Amber largely to its own devices, Llewella's interest in Rebma and its client worlds is intense and proprietary. Where Random maintains his sway over the Family largely by presuming it so strongly that nobody wants to contradict him, Llewella questions everything, especially why the Family is lining up behind the one of them that they swore they'd never trust. Strangely enough, this has let her slowly craft a place for herself, if not in the center of the court, at least at its fringes. She questions, and sometimes her questions have great wisdom. Currently she jockeys with Gerard, who has fallen from a position of influence to the point where she might reasonably benefit at his expense... perhaps even enough to gain the King's ear.
Random: King Random, by the by. He is the one who was never fit to rule, who even counted himself out of the great game. He is a lover of Shadow and all its potential. He is a King who has avoided catastrophe, but has also avoided greatness. One or the other will eventually be thrust upon him, of course. He is always ready to tell you where Amber's best interests lie... and to assume that you will do the right thing, given that knowledge.