Yeah, on the layer stackup dialog, you can set mechanical pairs. What happens is you get the next sequential layer assigned for the opposite layer. That is, if you have layers 1, 3 and 15 present in the footprint, the opposite side will use 2, 4 and 16 (assuming you assigned them all).
It's usually okay to print assembly outputs with components only on top / bottom layer, but pairs usually gives better results. Worst example is when making a composite print, all the shapes and pads of components on the hidden side are omitted fully, even if they affect the layer of interest! So you get what looks like traces running to nowhere, when actually there's padstacks and a connector there.
Tim