Originally Posted by IFW
Actually you can go for 64 colours (half of them are shades of their parent colour though), I did for AP2, if you really want ocs, also you should split the interface to be on the bottom or top of the screen and you can change the complete palette for that, only the pointer colour must be shared, the rest can change within the very same screen easily. Also instead of using gradients in the gfx (sky etc) you can change some selected colours on each scan line. You can also change the palette partially if you really want to, but that will take away most of the cpu cycles when the copper takes the bus.
Great if you're writing your own engine in C or assembly; not so good if you're using GRAC, which was written in AMOS, which in turn was written for the OCS chipset. You're limited to 320x256 in 32 colours, and those have to come from the 12-bit OCS palette, not the 24-bit AGA palette. GRAC doesn't give you access to any raster or copper effects (even if AMOS had them in the first place, which I'm not sure about).