Sorry to say this, and its not because I dont like Oscars.
Get rid of the Oscars, and buy yourself something different. All small, say 2" and smaller. You could put in there a dozen to 20 small Cichlids. Throw in a couple exotic plecos, a couple cool looking loaches and maybe a Poly. ALL SMALL.
And enjoy watching them grow and interact. You can provide caves and hiding places, soon it becomes real enjoyable, because now your interacting with them. They start small, and get use to your ways. Yes they all will soon get larger. But you will have months of enjoyment. Then as the tank starts to get crowded, you can choose your favs and keep them and sell the rest.
I have a 135 as a grow out. I have 20 fish in there and it has been about 6 months since they all went in. The average size of fish is now 4" (they all went in at around 1"). I am overcrowded, and working to relieve that. But in a 210, you may have another few months to enjoy it all. Say 8 months. Who knows, after 8 months of enjoying them, it may cause you to want to set up another tank.
Well good luck in whatever you decide.