I try to make sure that Syd has space usually through the middle so that he can go from one side to the other uninhibited. Not that he flies with wings spread but he often goes with some speed. I find fewer toys but regularly swopped has been his happiest cage.
i would recomend putting a bit of stuff in the bottom maybe one daul a couple of naturals and two three toys since birds dont really use the bottom but that doesnt mean not to put anything there