AVR based PLC/relay board design - repost

I need an AVR and SIM900 based board designed. The SIM900 will have buzzer, LED for network status, power, etc. I am writing here Arduino Pins: ATMEGA328P with 16MHz crystal. The pins 0 & 1 are Rx and Tx respectively. These pins go to the SIM900 Tx and Rx respectively. The pins 2 & 3 will be opto coupled inputs just like the PIC PLC board you make. The pins 4 will be out to a pin header, with VCC and GND. (The pins 5,6,7,8, 10,11,12,13 goes to the ULN2803, the output of which goes to the 4 relays that are connected with 5,6,7,8. The rest 4 pins of the ULN2803 will just go to the Pin headers. This might change a little as I need only 4 relays so, we I will take the SPI pins out). The pin 9 will also go to a different pin header, like the pin 4 with its own VCC and GND. The A0, A1, A2 and A3 will again go out to a 4 pin header, with 4 rows of Vcc and GND. I would like a DS1307 RTC connected to the pins A4, A5 (SCL/SDA). The board will also have LM2596 based power supply. The relays would be the normal 12V sugar cube relays, with 4 relays 10AMPS There should be ISP pin headers also. Preferred 2 sided PCB with sufficient spacing between traces and large pads for easy soldering. Let me know, if you are interested, lets start will designing the schematics and PCB layout. I need the 3D model also.