That's a tough one, because Oscars are so ahead of other cichlids on the personality curve.
If you can afford them (and are willing to deal with fussy upkeep), discus are beautiful, and have sort of royal personalities. I do like severums a lot - they're like discus without the difficulty - I've had gold and green/wild ones and loved them both.
I have had very personable green terrors and dempseys, but you might get a shy or aggressive one too. I have a mated Dempsey pair in a 40 now, and I love them, but they hide together a lot.
Lastly, you could try a group of smaller cichlids like rams (which I love to admire in other tanks but know ZERO about) or a group of earth eaters (geophagus - ask around to find out which ones won't get too big).
Good luck
