I agree, get an aftermarket deck that can play MP3 CD's, has a USB interface and is iPod compatible. Beware that some decks say they are Bluetooth and satellite compatible but actually require an accessory to be compatible.
I have a Kenwood deck that cost me $200. I can play MP3's from CD or a USB stick and I can plug in an iPad into the USB port and control the iPod from the deck. What really sold me on the Kenwood was the fact it came with a remote control. Men luv their remote controls
To install an aftermarket deck you'll need an installation kit to make it fit ($20) plus adapter harness's for the electrical & antenna. The Liberty's stock antenna lead is unique.