Suggestions and opinions about my robot

Hi all,

I am designing a prototype based on microcontroller Atmega328. It also will included a L298Dual Full Bridge Driver and a Xbee module. The idea is to design something like an all-in-one little PCB in order to build a remote control Arduino based car.
In the attached image, you can see first schematic attempt. Although I have experience dealing with electronics, it’s my first project like that from scratch.
So I would really appreciate your comments/opinions and suggestions. All reviews and improvements are welcome.

Best Regards