This is a 7-hr-combo tour of both Sugar Loaf and Corcovado (Christ statue), with a city-tour, a brief visit to Rio's Tijuca forest. One could have a snack at the waterfall in said forest.
Since you'd be paying by the hour, here you can design your own tour, assisted by my expert suggestions, if you so require.
It'd be a day to remember, I assure you.